Basics of Electricity
Electrical Engineer's pocket guide you have to register but it is worth the effort! Thanks to IDC Technologies.
Power Factor Correction & Energy Savings - Harmonics - a misunderstood phenomenon - Jean-Guy Boudrias & Jeff Barnnard - Harmonics in electrical distribution systems are created from a number of sources and produce a variety of undesirable side effects, therefore it is important to understand all solutions that are available. Phase shifting will be reviewed as one concept for solving certain types of problems related to power quality . Both theoretical concepts and a case study are presented - from United Wire & Cables.
The Differences between Watts and Volt Amps - Steve Mackay - I often get questions about the practical differences between watts (W) and volt-amperes (VA); mainly from our civil and mechanical engineering fraternity; but surprisingly also from some electrical types. As you would know, electrical products generally indicate both to show how much energy and current they draw. This Blog details a quick summary of the differences with some interesting alternative calculations to work out total VA.
Cable Tray
The following technical information is from the Cable Tray Institute
- What is a Cable Tray System?
- What standards / guidelines are available for cable tray systems?
- What types of Cable Tray are available?
- How do I know what type of cable tray is right for my application?
- What materials / finishes are available for the various cable tray systems?
- Now that I know what types of cable trays are available, what configurations are available?
- After selecting the type of cable tray and configuration required, what support methods are available?
- Before selecting the type of cable tray, cable tray configuration(s), and support method desired, what additional information do I need to supply to the cable tray manufacturer for them to best understand and satisfy my needs?
Technical Papers from the Cable Tray Institute
- Paralleled Phase Conductors in Cable Trays Provide Copper Savings
- Thermal Contraction and Expansion of Cable Tray
- Moisture Problems in Electrical Systems
- Cable Tray Type Selection
- Tie Down Practices for Multiconductor Cables in Cable Trays
- Circuit Integrity of Cable Tray Wiring Systems During Natural Disasters
- Caution in Using Cable Tray Covers Outdoors
- Bonding Jumpers Not Required for Standard Cable Tray Splice Plates
- Cable Tray Wiring Systems Have Many Cost Advantages
- Cable Tray Systems in Ducts, Plenums and Other Air Handling Space
- Equipment Grounding Conductors for Cable Tray Systems
- Grounding Inspection of Steel & Aluminum Cable Tray Systems
- Hot Dip Galvanized vs. Aluminum in Outdoor Application
- Cable Tray Width Selection for Installation with 600 Volt Single Conductor Cables
- Cable Tray Grounding: Power, Instrumentation, and Telecommunications
- Types of Cabling Used in Cable Tray
Identifying Tray Cables for Your Next Installation - Though rapidly increasing in popularity, tray cables are still a point of confusion for many. While the term “tray cable” is being heard everywhere, many do not understand what exactly a tray cable is or the benefits of using tray cables. Another gray area for many comes from the variety of types of tray cable, what each means and in which applications each type should be used. This paper defines what a tray cable is, describes the different types of tray cables, provide uses and standards for each type of tray cable. It will also provides a reference guide regarding the applications and governing standards for each tray cables type - from Turck.
The National Electrical Manufacturers Association (NEMA) has published NEMA VE 2-2013 Cable Tray Installation Guidelines. The fourth edition of this publication, VE 2 is a practical guide for the proper installation of cable tray systems.This publication addresses shipping, handling, storing, and installing cable tray systems. Information on maintenance and system modification is also provided. Cable tray system design must comply with National Electrical Code® Article 392, NEMA VE 1 Metal Cable Tray Systems, NEMA FG 1 Fiberglass Cable Tray Systems, and follow safe work practices as described in NFPA 70E Standard for Electrical Safety in the Workplace. The guidelines in this publication are useful to engineers, contractors, and maintenance personnel.NEMA VE 2-2013 has been revised to reference the 2011 version of the National Electrical Code® and provides clarification for grounding and bonding cable trays, as well as recent cable tray product developments. NEMA VE 2-2013 Cable Tray Installation Guidelines may be downloaded at no cost on the NEMA website or purchased in hardcopy for $88.
Cables
Cables-IEEE 1242 Specifying and Selecting Cable for Petrochemical Plants a Guide - By Donald A Voltz and Joseph H Snow, this is a really excellent technical paper from Mustang Engineering.
Protection or Degradation - Separate the ‘quiet’ cables such as analog I/O lines, digital I/O lines, or LAN connections - Motors starting, stopping, switches on and off, controls blinking in and out … it is a cacophony of electrical clatter. In today’s industrial environments, electronic devices, signal and power wiring, and other electrical plant/process equipment often interact to create “noise” or electromagnetic interference (EMI) problems, which can degrade critical measurement and control signals. Proper grounding and shielding techniques can help reduce or eliminate these problems and maintain signal integrity. From InTech.
How to Stop the Noise with Shielded Cable - The Importance of Being Properly Shielded - Electrical Interference or noise is the bane of all complex (and high speed) industrial electronics system and product designers. And why not? In Industrial controls systems, for example, it's estimated that well over 50 percent of all system hardware failures are caused in part by electrical noise. This is not just an issue for microprocessor based systems. With today's infinitely more complex communications and control systems that incorporate higher transmission and switching speeds, the implications of noise related failures are increasing exponentially. There is growing industry concern as well as increasingly more rigid regulations related to electrically radiated emissions, and EMC (electromagnetic compatibility). How to shield power and signal cables has never been a bigger issue. Based on the ever increasing distances that signal and control communications are required to travel, cables are the system components most highly exposed to interference. In fact, EMC and effective shielding have become just as critical as any other design concern, particularly in mission critical applications such as: medical, defense, industrial machinery, sensing and control, and communication - from Alpha Wire.
Heat-Shrink Tubing: The Versatile Tools for Maintenance and Repair - Think of heat-shrink tubing as the duct tape for electrical wiring on the factory floor. Heat-shrink tubing is versatile, easy to use, and finds wide applicability in maintenance and repair. Heat-shrink tubing can be used for preventive maintenance to avoid problems, and it is a wonderful tool for making minor repairs to cables and connectors - from Alpha Wire.
Specifying High-Performance Cables - The Devil Is In The Detail - Still, cables fail and systems go down. Why? Many of the problems that surround cable failure, especially in extreme and harsh operating environments could have been avoided by selecting the correct cable from the outset. "But specifying cable is easy," you say. Well, yes and no. Sure, it's easy to match temperature ranges and then count on a PVC jacket for protection. But there's a lot more to it than that. Understanding how the cable will work when exposed to extreme temperatures; quantifying the type of chemical, oil, fuel or solvent the cable will be exposed to; understanding the difference between flexible and flexing, considering the level of mechanical abuse, UV exposure and EMI/RFI interference concerns are just a few of the details that engineers need to consider before "fully" specifying an appropriate "hazard-matched" cable - from at.farnell.
Haloarrest® Low Smoke Zero Halogen Jacket Compound - Sarah Gladding - The Haloarrest jacket offers a unique solution to fit many applications. The Haloarrest jacket is a Low Smoke Zero Halogen (LSZH) alternative to traditional wire and cable jacket compounds. Cables with the Haloarrest LSZH jacket provide a useful alternative for industries that require restricted use of halogenated products. Materials that contain halogens emit potentially harmful and corrosive gases when they are burned. Haloarrest jacketed cables offer excellent flame resistance, low smoke properties, and reduced toxicity. From Beldon.
Low Smoke IEC compliant Non Halogen Cables Provide Maximum Safety and Assurance - Awareness of the impact of smoke and harmful gases emitted during a fire has led to a growing demand for an alternative to the more traditional plastic halogenated cable constructions. PVC has long been used as an appropriate cable insulation and jacketing material with a high degree of flame-retardancy. However, in the event of a fire this will generate dense black smoke, with toxic and corrosive gases that can cause fatality and destruction. This fatality and destruction is attributable to the significant amounts of halogens, namely chlorine, found in PVC based compounds. On combustion, lethal gas is released, which on contact with moisture produces copious amounts of hydrochloric acid. Particularly hazardous in areas of minimal ventilation and restricted escape, the dense black smoke impairs visibility and means of escape, equipment will be damaged by the corrosive gases whilst the effects of inhalation of toxic gases can be fatal. Flame retardancy is important but so is the choice of a cable that emits smoke in very low levels and more importantly - without harmful corrosive and toxic gases. Despite stricter legislation and a more responsible attitude, lives and equipment are still put at risk due to the use of halogenated cables or cables that scarcely meet recommended industry standards - from Beldon.
How Wire Fails - Stephen H. Lampen - Wire and cable can fail from a number of causes. This paper is an overview of the various failure modes wire can exhibit, how to predict each and how to help prevent it. Often, installers or users mistakenly suspect one failure mode when in fact another (or even none) is to blame. This article will also present an analysis template to determine just which failure mode might be expected.
Cable Alternatives for PWM AC Drive Applications - This paper describes an alternative solution for cables used with Insulated Gate Bipolar Transistor (IGBT) Variable Frequency Drives (VFDs). New IGBT technology has introduced voltage stresses on motors and cables that leads to unpredictable system performance and reliability. This paper includes a performance and cost comparison between a continuously welded armored option, the option of lead wire in conduit, and a proposed shielded tray cable. Unique physical characteristics of the cables are discussed. A proposed cable with increased insulation thickness is discussed that insures long-term cable service life under VFD operation, while the shielded coaxial braid contains VFD EMI emissions. Other applications, options, and termination considerations with respect to the petro-chem industry is discussed. Cable performance is documented with theoretical and experimental support.
Building a Reliable VFD System - Brian Shuman - Special consideration must be given to the proper installation and operation of the overall system that comprises the VFD, the motor it controls, and the cable that connects them. From Belden.
The Adventures of Conduit Phil - Stephen H. Lampen - So you're designing your install and you have a choice: conduit or non-conduit. A lot of cable today is made non-conduit, (i.e. "plenum rated"). This is almost always a better deal. Plenum-rated cable can go anywhere you want it to. Cable in conduit can only go where the conduit goes. There are almost no limitations on how much plenum cable you can put in a drop ceiling. Cable in conduit is limited by the size of the conduit, and big conduit is mighty expensive. It's easier to install plenum cable (not to mention the cost of conduit installation), so your labor costs will be a lot lower. You can add, change or modify an installation of plenum cable easily ... just add another cable. With conduit, you might have to add new conduit. Not a simple task. From Belden.
Pyrotenax® MI Cable Industrial Wiring Installation Manual - This manual covers storage and installation of Pyrotenax Alloy 825 Sheath MI industrial wiring cables. It is assumed that the cables have been correctly sized and the installation properly designed. From Tyco.
Best Practices for Process Instrumentation Cabling - Saeed M. AL-Abeediah - This article looks at the classes of instrumentation circuits and wiring suitable for each class, signal noises, techniques that minimize the impact of noise and interference on instrument signals, and conclude with a proposed process automation grounding scheme that PAS vendors helped develop - from ISA.
Identifying Tray Cables for Your Next Installation - Though rapidly increasing in popularity, tray cables are still a point of confusion for many. While the term “tray cable” is being heard everywhere, many do not understand what exactly a tray cable is or the benefits of using tray cables. Another gray area for many comes from the variety of types of tray cable, what each means and in which applications each type should be used. This paper defines what a tray cable is, describes the different types of tray cables, provide uses and standards for each type of tray cable. It will also provides a reference guide regarding the applications and governing standards for each tray cables type - from Turck.
What to Know When Selecting Your Cable Solution - When selecting the proper cabling for industrial applications, it is important for users to consider performance strengths and limitations associated with each cable solution in order to select cabling that meet an application’s exact needs. This white paper will address the differences between AWM recognized cable and UL listed cable, describing the testing requirements listed cables must satisfy and highlighting the benefits associated with ITC and PLTC cables, such as durability, reliability and longevity - from Turck.
The following links are from Olex Australia
Cable Terminology - A list of common Terms.
- How do I determine the rating of a cable?
- How do I measure the amount of current a cable can carry over a particular distance?
- How do I determine the size of cable required for a particular current of a distance?
- Are orange circular PVC cables suitable for use outdoors exposed to sunlight? Is the orange PVC “UV stabilised”?
- What is the correct lug for use on compacted conductors?
- What is the correct lug for use on flexible conductors?
Instrumentation
- What is the purpose of the screens in instrumentation cables?
- Why are there individually screened pairs or triples as well as overall screened pairs or triples?
- Data cables have screens also - what is the difference between a data cable and an instrumentation cable?
- There are cheaper instrumentation cable types available in the market. What are the differences?
- Are Instrolex cables manufactured to any standards and do they comply with the Hazardous Area Standards?
- What is the voltage rating of Instrolex cables?
Flexibles
- Why are some conductors tinned and others are not?
- What is the difference between a cord and a cable?
- Flexible cables are often used with oil or chemicals. How do you determine which cables will be suitable for these applications?
- Why don’t manufacturers mix PVC and rubber in building a cable? For example, a PVC insulation and CSP sheath.
- What type of flexible cord or cable is used on hot appliances?
- Are the Olex 4 core flexible cord core colours (Brown, Light Blue, White, Green/Yellow), in contradiction with AS/NZS 3000?
- Can I use Flexolex® in reeling applications?
- Why would a contractor want to use a flat sheathed cable instead of a circular cable?
- PVC is available at various temperature ratings, ie 75°C, 90°C and 90°C-HT. As XLPE is rated at 90°C what's the difference between that and the higher rated PVC?
- Does the change of V105 to V90-HT mean that this grade of PVC has been down rated?
- What does the .6/1kV designation mean?
- Why are generally used cables designated as 450/750V when only 240 volts are being carried?
Fire Rating - A series of questions covering;
- If a cable has a fire rating, does this mean that it won’t burn?
- Can a cable with a fire rating operate continuously in hot environments, for example, very close to a furnace?
- What does a two hour fire rating mean?
- How is the resistance to mechanical impact measured?
- What does the cable system consist of?
Designs and Reliability of Underground Cables and Systems - Hilary Marazzato and Ken Barber - The excellent electrical performance of XLPE is the reason it is now used almost exclusively for insulating low voltage, distribution and transmission cables. While XLPE has far better resistance to moisture than paper insulation or PVC, moisture can affect long term performance of XLPE under the influence of high electrical stress. All low voltage and distribution cables can be installed without precautions, but some moisture protection is advisable for medium voltage cables and cables for sub-transmission. The use of metal sheaths for transmission cables is considered essential.
The Changing Pattern of Power Cables - Discussion on Power Cables with Flexible Conductors - This paper discusses currently available technology, the shortcomings, and the trends for future development.
Cable Condition Monitoring to Improve Reliability - Hilary Marazzato, Ken Barber, Mark Jansen, and Graeme Barnewall - The electric cable industry is definitely in the mature product stage and while there are many incremental developments and improvements, the history and experience gathered enables us to approach issues of cable failure and cable life maintenance with ever improving tools. This paper discusses currently available technology, the shortcomings, and the trends for future development.
Global Trends and Motivation Toward the Adoption of TR-XLPE Cable - P.J. Caronia, A. Mendelsohn, L.H. Gross, J.B. Kjellqvist - Dow Chemical Company - This paper discusses the multitude of accelerated cable aging tests, implications and current global trends for both the TRXLPE and the Copolymer XLPE insulations.
Underground High Voltage Cables: Wiring Europe for the Future - Take a look at the many benefits of underground high voltage cables and learn how they can be put to work for you - From The European Confederation of National Associations of Manufacturers of Insulated Wire and Cable.
Specifying Cable for your Next Design - Designers working on products involving cables may find themselves faced with a multitude of considerations before making a cable specification. It's often a good idea to identify some of the major deciding factors before proceeding: for instance, whether the final product is destined for domestic (North American) or international use. From there it's possible to determine whether cable is needed at all, and then to analyze which type or types of cable may be necessary. From Interpower.
Specifying Armoured Instrument and Control Cable - Greg Passler - It’s sometimes difficult to wade through the myriad of options and features available when selecting a control or instrumentation cable for your application. Despite the variety, choosing the more popular attributes and understanding the reasons for doing so will make your task much easier - from Shawflex.
The following papers are from American Polywater.
Estimating Tension When Pulling Cable into Conduit - When you calculate cable pulling tensions, what friction coefficient do you use? Field responses vary . . . some answer ".5" . . . others ".45," ".4," or ".35" . . . and, recently, a European engineer responded "usually .2 to .3." Who's right?? What coefficient of friction should you use in pulling equations to provide the best tension estimates for better field planning and electrical system design? - from American Polywater.
Electrical Cable Cleaning Video - For High Voltage Electrical Splicing - This 8-minute training video on CD demonstrates high voltage cable cleaning procedures during splicing and termination. Methods are shown to remove different types of shields and compounds from insulation. The "Do's and Don'ts" of solvent spraying, and cleaning techniques are presented, including safe methods for using SpliceMaster® cleaning solvents - from American Polywater.
Cable Installation Engineering Video - This 13-minute training video examines the engineering aspects of installing cable in conduit. Topics covered include the nature of cable pulling friction; using software to estimate pulling tensions, determine pull feasibility, and design optimal cable runs; the causes of cable failure; cable/lubricant compatibility; lubricant residue combustibility; cable lubricant specification; and more.
Combustible Cable Pulling Lubricant Residue Can Spread Fire! - Well over a decade ago, fires at the Brown's Ferry Nuclear Plant in Alabama and skyscrapers in New York City focused the attention of cable manufacturers and design engineers on the spread of fire through cabling systems. Today's fire-retardant cables are made from specially-formulated, fire-resistant materials. They are tested to special industry specifications. These state-of-the-art, fire-retardant cables show little tendency to ignite and propagate flame, and, thus, do not support the spread of fire. It is common practice to specify fire-retardant cables, as well as "fire stop" materials, to prevent flame from spreading through electrical penetrations in fire-resistant walls, etc. The prevention of fire spread is addressed in the National Electrical Code (Sec. 300-21), as well as numerous building codes and industrial standards. Prevention of flame spread is also desirable for cable pulling compound residue, since they, too, can be present throughout a conduit system.
The following Technical information is from Northwire Inc.
Cable Fables - Confusion and Misconceptions about NFPA-79 - Confusion abounds about the “new” NFPA (National Fire Protection Association) regulations pertaining to UL-recognized (AWM style) cable. Long after the practice became widespread, inspectors became aware of the ubiquitous use of AWM (Appliance Wiring Material) style cables in machine interconnecting sensors, actuators, switches and other components—often as part of premolded connector assemblies. The 2007 change to the NFPA-79 electrical code states that AWM-style single-conductor wire or multi-conductor cable is not permitted on machinery unless it is part of a UL-listed assembly. In other words, machine wiring requires UL-listed cable. Clearly, UL-listed cable has been available for many years. So the real question is, which UL listing is appropriate for particular applications?
Flame Testing - Testing for Flame Resistance of Electrical Cables - Harold Gjerning - Agency Compliance Technician - The National Fire Protection Agency (NFPA) publishes flame-resistance standards through its published National Electrical Code (NEC). Other agencies, such as UL and CSA also publish standards and also define certain tests for determine flame resistance (or lack thereof). Flame resistance requirements are for the most part governed by local and national codes which define the various levels of flame hazard, plus the severity of the fires to which cables may be exposed. The important considerations are propagation of flame, support of further combustion, generation and propagation of smoke. The NEC deals primarily with fire hazards in buildings, whereas UL and CSA deal with requirements based on use.
Custom Cables for Medical Applications - Medical cables have to meet requirements that are more demanding than the non medical variety. This article discusses these.
Slimmer Cables Can Take More Flexing
Selecting the Right Cable for Foundation fieldbus Control Networks - What you need to know - Sandy Fulton - FF-844 is the Fieldbus Foundation cable compliance specification. FF-844 includes the electrical requirements of ISA 50.02 and IEC 61158, but it also contains some additional requirements which help you know your cable is the right cable for use in FOUNDATION fieldbus control networks.
Cable Innovation Makes Industrial Networking Faster, Easier & More Reliable - Cable Innovation Makes Industrial Networking Easier, Faster and More Reliable - As engineers and systems integrators gain experience with FOUNDATION™ fieldbus installations, they are realizing the advantages of multi-pair fieldbus trunk lines in plant installations. These users are simplifying installations by merging formerly scattered control and instrument points into common bus segments and junction boxes. The benefits include installation cost savings, more compact cable housing in a tray or conduit and neater assemblage in the junction boxes. Instead of running bundles of single-pair trunk lines, cable specifiers are requesting multi-pair fieldbus trunk cables.
Know Your High-Flex-Life Cable - When your application calls for cable meant to stand the tests of time and motion, you need to know what topurchase and what constitutes product quality. Cable designed to survive 10 million to 20 million flexing cycles is high-flex-life cable. It’s different from high-flex cable, which is designed to be supple and highly flexible. High-flex-life cable may actually feel stiffer than high-flex cable. The two products are distinctly different and mutually exclusive. Try bending the cable, twisting it, pulling it, rolling it back and forth in a track, having it bear weight, rubbing it and subjecting it to extremes of temperature and to solvents, oils and chemicals. Now do these things 10 million times in continuous motion, without ceasing. You’ll learn the difference between highflex- life and high-flex cable quickly - one cable isn’t the same as the next.
Why Order Custom Cable? - Ted Beach - A project engineer can choose off-the-shelf cable - the manufacturer's way - and then adapt it to specific needs, or that same engineer can choose custom cabling designed for a specific purpose - the project engineer's way. There are advantages and disadvantages to both choices. this article reviews these.
Cable Goes Twist Friendly - Constant motion can turn ordinary wiring into a big maintenance item on equipment. Read how continuous motion can destroy ordinary cables and what Northwire is doing to produce cable that will last millions of twist, roll, and bend cycles. Consider how typical industrial-automation equipment works today. Most of it is in use nearly 24/7. It frequently contains robotic elements and assemblies that execute motions repeating hundreds of times or more every minute. No question that these applications put stringent demands on moving parts. This is true even for the cabling that connects moving equipment to controls. This cabling can see millions of flex cycles in the course of normal use. From Machine Design.
Out of the Frying Pan and onto the Cable - Teflon®and Other Fluoropolymers - Teflon, a product developed by DuPont and a common coating on cookware, is one of a group of compounds known as fluoropolymers. Fluoropolymers are fluorocarbon-based polymers with multiple strong carbon-fluorine bonds. Teflon FEP - a different grade than the product used on cookware and other fluoropolymers possess special electrical properties and have a high resistance to solvents, acids and bases. These and other characteristics make fluoropolymers ideal materials used in the manufacture of wire and cable products.
Current Capacity of Copper Conductors
The Following Papers are from Olex New Zealand
Long Term Sustainability of Cables - David Griffiths - This is an excellent paper covering many aspects of cables and cabling.
Why Not Underground - David Griffiths - Underground cables need a proper burial so therefore the engineer must possess sufficient background knowledge in cable construction, the installation design, actual installation, testing, and maintenance of the underground cables.
The Following useful information is from Caledonian Cables
Cable Standards
General Standard
Material Standard
Fire Performance Standard
UK Standard
UL Standard
EN Standard
Cable Colour Code
Cable Testing & Fire Resistant Cable
Test Method for Fibre Optic Cables
Introduction to Fire Resistant Cable
Fire Performance Testing
Emission of Smoke, Halogens and Toxicity Testing
Cable Glands
Why Should You Specify Cable Glands? - How often have we heard:- "We don't specify Cable Glands, as long as they have the relevant certification then it must be fit for purpose. We leave it to contractor to sort out. We are too busy concentrating on the high value, long lead time items to bother about such an insignificant value product. In a recent paper presented at the Hazard Ex conference by a Senior Manager of CENELEC Standards Inspections, it was stated, "Resources should be directed at eliminating the following common faults; Unauthorised modifications, badly made-off or unsuitable cable entry devices and Corrosion. It went on to say that out of these three factors, the most common fault was bad installation of Cable Glands. The paper was specifically referring to maintenance procedures, but this could equally be applied to new installations. Incorrect specification and installation combined with the lack of ability to inspect the Cable Gland in it's operable condition can cause equipment failure and corrosion of cable armour and braid. The safety risks inherent in this is incalculable, as is the consequential loss of production. This statement alone should be enough reason why specification of Cable Glands is an important decision. Just relying on the fact that a Cable Gland has a certificate "fit for purpose" is not enough - from Hawke International.
Armoured Cable Glands - Covers; Reasons for using Cable Glands, Standard for Cable glands, Selection of Cable Glands, Barrier Glands and Gland Sizing - from Control and Instrumentation.
Cable Drum
Drum Schedule - Comprehensive Learning Guide - Drum scheduling is a logical process of putting together pieces of cables to make a spool of cable. Procurement of cables is generally transacted in unit of drum. During construction stage, the lay out (pulling) of cables are drawn out and cut from the drums. For these reasons, proper drum management is necessary to facilitate the procurement processes and to maximize the usage of the cable in the drums - from ELTECHS Engineering & Consulting Co., Ltd.
Cable Drum Handling - A Cable is a valuable product. If handling is not done correctly, the drum and in turn the Cable wound over it can be damaged. At times, damage might not be discovered until after installation, when repairs can be extremely difficult / expensive. The purpose of this guide is to illustrate, how damages can be avoided by correct handling and storage practices - from Gulfcable.
Fibre Optic Cables
Reference Guide to Fiber Optics - This is the Fiber Optic Association's Online Reference Guide. It includes materials from the basics to advanced topics on fiber optics and premises cabling that are to be used as reference materials for those working in the industry, studying for FOA Certifications, for FOA training classes and refresher tutorials for FOA CFOTs.
Optical Fibre Cable - Covers Design, Reliability and Quality, Cable Types, Jacket Material, Colour Coding, Propagation Speed and Delay, Losses and Safety - from Wikipedia, the free encyclopedia.
Optical Fibre Specifications - The usual fiber specifications you will see are size, attenuation and bandwidth. While manufacturers have other specs that concern them, like numerical aperture (the acceptance angle of light into the fiber), ovality (how round the fiber is), concentricity of the core and cladding, etc., these specs do not affect you. Covers fibre types and Specifications - from LANshack.
Guide To Fiber Optic Network Design - What is “fiber optic network design?” Fiber optic network design refers to the specialized processes leading to a successful installation and operation of a fiber optic network. It includes determining the type of communication system(s) which will be carried over the network, the geographic layout (premises, campus, outside plant (OSP, etc.), the transmission equipment required and the fiber network over which it will operate. Next we have to consider requirements for permits, easements, permissions and inspections. Once we get to that stage, we can consider actual component selection, placement, installation practices, testing, troubleshooting and network equipment installation and startup. Finally, we have to consider documentation, maintenance and planning for restoration in event of an outage - from the Fibre Optic Association.
Fibre Optic Installation - Problem or Opportunity - Increasingly, electrical engineers and installers are becoming involved with fiber optic cable, from a specification, design, and installation standpoint. Misconceptions are common about fiber optic cables themselves, how their handling differs from electrical cable, and how to plan and make high quality fiber optic installations. This "Technical Talk" will focus on installation of fiber optic cable in conduit, contrasting it with electrical cable. The types of fiber available (single mode, multimode, etc.) and the various cable constructions (loose tube, tight tube, armor, etc.) are beyond the scope of this discussion. Please be aware that there are a great number of fiber cable types and constructions, and the discussion can only cover general principles of application for most fiber optic cables - from polywater.
Analysis of Duct Placement Factor in Fibre Optic Pulling - Many fiber optic outside plant installations involve long "straight" runs of cable pulled into duct. The pulling equations have shown good tension prediction ability in the installation of heavy cables in straight runs. However, these same pulling equations predict that fiber can be pulled much longer distances than today’s reality. Based on simple friction theory, it should be possible to pull fiber cable, with a weight of 100 to 200 lbs/1000 feet (150 to 300 Kg/Km), in the range of 15,000 to 30,000 feet (4.5 to 9.0 Km) with pulling forces under 600 lbs. This assumes friction coefficients under .2, which are routinely measured with our Polywater® Fiber Optic Lubricants. But experience shows that maximum pulling distances of 3000 to 6000 feet (1 to 2 Km)--at under 600 lbs (2.7 Kn)--are more realistic, even with a new, properly placed duct system. What produces this error of a factor of 5 or more? - from polywater.
Calculating the Maximum Attenuation for Optical Fibre Links - This document describes how to calculate the maximum attenuation for an optical fiber. You can apply this methodology to all types of optical fibers in order to estimate the maximum distance that optical systems use - from Cisco.
The Fiber Optic Association - The FOA is a international non-profit educational organization that is dedicated to promoting professionalism in the field of fiber optics through education, certification and standards.
Air Assisted Fibre Optic Cable Installation - High Air Speed Blowing, Air-Assist, Push/Pull Installation, Air Blown Cable, and Cable Jetting; all describe new methods to get cable into conduit using air. To date, the primary use of these methods has been to install fiber optic cable. Air-assisted fiber optic installation was developed and explored in the Netherlands as well as the United Kingdom in the 1980’s. While blowing methods are used to install individual fibers in tubes in LAN’s, this article will focus on the outside plant installation of jacketed, multi-fiber cable in duct. While this is typically underground duct, blowing will work for aerial duct installations as well - from American Polywater.
Tray Cables
How Do you Identify the Correct Tray Cables for your Next Application? - The term tray cable is being heard everywhere but what exactly is a tray cable and what are its benefits? This educational paper from Turck will:
- Define what a tray cable is
- Describe the different types of tray cables
- Provide uses and standards for each type of tray cable
Circuit Protection
The 12 Most Common Mistakes of Specifying Circuit Protection for Equipment - From ETA Circuit Protection and Control.
The following excellent protection articles By GEORGE W. FARRELL and FRANK R. VALVODA, P.E have been issued by the folks at the Consulting Specifying Engineer website http://www.csemag.com.
The Art of Protecting Electrical Systems, Part 1: Introduction and Scope
The Art of Protecting Electrical Systems, Part 2: System Analysis
The Art of Protecting Electrical Systems, Part 3: System Analysis
The Art of Protecting Electrical Systems, Part 4: System Analysis
The Art of Protecting Electrical Systems, Part 5: System Analysis
The Art of Protecting Electrical Systems, Part 6: System Analysis
The Art of Protecting Electrical Systems, Part 7: Equipment Short Circuit Ratings
The Art of Protecting Electrical Systems, Part 8: Short-Circuit Calculations
Earthing
Electrical Earthing Systems - This excellent link from Wikipedia, the free encyclopedia is an excellent reference on electrical earthing and grounding. It includes information on Low-voltage systems, IEC terminology, TN networks, TT network, IT network, Safety, Regulations, Application examples, Medium-voltage system, Solid-earthed neutral and Unearthed neutral.
Earthing in Low Voltage Systems - Covers Earthing connections, Definition of standardised earthing schemes, Characteristics of TT, TN and IT systems, Selection criteria for the TT, TN and IT systems, Choice of earthing method - implementation and Installation and measurements of earth electrodes - from Schneider Electric.
Understanding Neutral versus Ground when applying RFI filters in Electrical Equipment Installations - The grounding of electrical equipment is probably one of the least understood aspects of electricity. As the characteristics of electrical equipment changes from linear to non-linear, the nature of grounding expands from the task of insuring the safety of personnel to insuring that one type of electrical equipment does not interfere with other types of electrical equipment. One point for confusion rests with the often interchanged terms of Neutral and Ground. Many articles have been written concerning the problems with 3rd harmonics overloading the neutral conductor. Many articles have been written concerning the problem of electrical ground noise. Even with all these articles, there still exists confusion concerning whether equipment should be connected to the neutral or connected to a ground. It may be possible that a simple rule would clarify the differences between Neutral and Ground. It can be stated that Neutral can be grounded, but Ground is not neutral. From Rockwell Automation.
The Following Excellent papers are from IDC.
- Reducing Copper Theft in Telecommunications and Electrical Industry - Rohit Narayan - ERICO - With the increase in copper prices, copper theft, which was once a nuisance factor, has now become a major problem for the telecommunications industry. Copper theft in the US alone has a cost impact in excess of US1 billion dollars per annum. Copper theft in the telecommunications and power sector includes the theft of ground bars, cables and grounding conductors. It is a significant problem in Australia and now extend to all the states - Thanks to IDC.
- Protective Earthing, Impacts, Myths and Verification Tests - Paul Lo - MIE Aust., Chartered Professional Engineer - Protective earthing is essential for electrical safety and power system reliability and stability. The effectiveness of protective earthing design and installation affects not only the adequate clearance of the life critical electrical faults, but also the power system reliability and availability. The ineffective protective earthing will lead to the potential hazardous ground voltage (potential ) rise during the ground fault and the prolonged ground potential rise (GPR) will have significant impact. Supporting diagrams can be found here.
- Best EMC Installation Practice for Variable Speed Drives - Understanding the Main Differences and Goals between Earthing and Bonding - Eduardo Gie - Technical Manager, Danfoss Pacific - Power Electronics - The application of variable speed drives (VSDs) or/ variable frequency drives (VFDs) are well-known for their benefits. They are energy efficient and flexible in the controlling of processes and machinery using standard AC or PM motors. Although many VSD’s can provide efficient control, depending on the design and installation of the VSD, they may result in increased problems elsewhere in the electrical system. When electrical noise problems arise, it can result in unreliable operation of other equipment, increased liability, increased project timescales and result in non-compliance with regulatory requirements. It can cause loss of revenue, since it can be a very time-consuming and a costly exercise to resolve them. This presentation highlights the recommended EMC best practice to avoid undesired Electromagnetic interference when installing VSDs in commercial and industrial applications.
Electrical Documentation
The Following Extremely Useful Documentation Tools are from www.industrialtext.com.
Electrical Relay Diagram and P&ID Symbols
Logic Symbols, Truth Tables and Equivalent Ladder/PLC Logic Diagrams
Programming and Documentation Pads (ALL)
These useful PLC listing pads allow you to implement better PLC design implementations and keep an orderly documentation system. Select a PDF with all listing and sample pads or individual listings with samples (below)
Electrical Lighting
How much does it cost you to change a light globe? - Do you want to dramatically reduce your lighting maintenance costs and reduce your risk hazards? Lighting maintenance is a necessity and often an expensive job in the industrial work place today. The costs involved are usually high due to the positioning of light fittings. This no longer needs to be the case. The installation of an In2 Light Hatch® will dramatically reduce the costs involved in changing light globes on industrial work sites.
Review of Emergency Lighting and Way Guidance Systems for Offshore Structures - This 86 page document prepared by the HSE UK presents a review of emergency lighting and way-guidance systems for offshore structures, carried out by the Environment Group and the Fire Research Station of the Building Research Establishment, for the Health and Safety Executive Offshore Safety Division and managed by the Marine Technology Support Unit.
Electrical Motors
Motors - Erik Mertens -The scope of this document is to introduce the basic principles of motors and its important characteristics as well as the possibilities to drive equipment. The motor driven equipment on a typical industrial site accounts for approximately two thirds of the electricity consumption. Therefore, any type of measure taken to improve the efficiency of a motor system consequently can offer major energy savings - From Laborelec and Leonardo Energy.
The Following Technical Papers are from Rockwell Automation
- A Comparison of the Characteristics of AC and DC Motors - As AC motors continue to be used in applications traditionally served by DC motors, some comparisons of the characteristics of AC and DC motors seem appropriate. The aspects of AC and DC motors which will be reviewed include typical construction, torque production, equivalent circuits, ratings (power and torque density), speed ranges, load ranges, etc. This comparison will also highlight some of the relative advantages and disadvantages of each type of motor in variable speed applications. In addition, looking at variable speed AC motors with a “DC motor mentality” can offer a more “user-friendly” understanding of these AC machines. This point of view can also suggest ways to optimize AC motors for variable speed applications.
- What Is Regeneration? - When the rotor of an induction motor turns slower than the speed set by the applied frequency, the motor is transforming electrical energy into mechanical energy at the motor shaft. This process is referred to as ‘motoring’. When the rotor turns faster than the synchronous speed set by a drive output, the motor is transforming mechanical energy from the motor shaft into electrical energy. It may be a ramp to stop, a reduction in commanded speed or an overhauling load that causes the shaft speed to be greater than the synchronous speed. In any case this, condition isreferred to as "regeneration".
- Drive and Motor Basics - An adjustable speed drive is a device that controls speed, and direction of an AC or DC motor. Some high performance drives are able to run in torque regulation mode.
- Motor Load Characteristics - Motor loads are classified into two main groups depending on how their torque requirement varies with operating speed. The following paragraphs deal with the various load types found in industry.
- Power Distribution Systems - The type of transformer and the connection configuration feeding a drive plays an important role in its performance and safety. The following is a brief description of some of the more common configurations and a discussion of their virtues and shortcomings.
- Dealing with Power Factor Correction Capacitor switching and AC drives - There are two significant concerns regarding the existence of power factor correction capacitors being located on the input of an AC Drive. One concern is the additional current loading that may exist in the capacitor. The other concern occurs when capacitor switching is used to adjust any variations in the power factor of the motor load.
Embedded Motor Condition Monitoring, Diagnostics - Adam Krug - Embedded condition monitoring and remote diagnostics prevent equipment failure, reduce energy consumption, improve reliability. Only a very small percentage of critical motors and motor loads in the U.S. actually are equipped with any sort of condition monitoring. This lack of adoption largely stems from the costs and complexity of conventional condition monitoring equipment. Industry-leading solid-state, motor control technology provides customers with the ability to monitor parameters, albeit not the exact same parameters, to gain a more precise and real-time perspective on performance, far more simply than traditional condition monitoring methods - from ISA.
Baldor has released a software estimating tool that enables users to evaluate the energy efficiency of electric motors and variable speed drives. Known as BE$T, the Baldor Energy Savings Tool can be downloaded free of charge from the company’s website. The software analyses the efficiency and annual electricity usage of users’ existing motors, and calculates the cost savings that can be achieved by replacing them with equivalent higher efficiency models. Built-in motor performance and pricing information enables the software to suggest optimum replacements and to estimate the investment payback period.
Electrical Drive Reference Centre - This Excellent Reference Site provides technical information on a range of different Electrical Motors.
Electrical Motors - Technical Articles - from the Electrical Drive Reference Centre.
Motor Tree - From SMMA - The Motor & Motion Association.
Motors-NEMA Terminations and Connections - from HUPP Electric Motors.
NEMA Frame Dimensions - Foot Mounted AC Machines, Type C Face Mounting Foot or Footless AC Motors, and Type D Flange Mounting Foot or Footless AC Motors - from HUPP Electric Motors.
Electrical Safety
Jump to the Various Sections of this page: Electrical Safety | Arc Flash | Digital Substation | Evaluating Fire and Heat Damaged Electrical Equipment | IEC61850 Based Process Bus Protection Systems | Power Transformers | Transmission Power Transformers |
Electrical Safety
The Following papers are from the 2013 Electrical Arc Flash Conference and Electrical Safety & Power System Protection Forum - Thanks to IDC Technologies.
Electrical Workplace Safety - Seven Electrical Safety Habits - Zarheer Jooma - Authored by Hugh Hoagland -This paper discusses seven electrical safety habits based on investigations of more than 150 electrical safety incidents and their the root causes.
The Dilemma of the Personal Protective Equipment Suppliers in Developing Countries - Ivan Pretorius Contracts Manager, Quality Safety - The dilemmas that suppliers find themselves in stem from the fact that they do not receive adequate information in order to meet their legal obligations regarding the supply of the correct Personal Protective Equipment. In order to assist in making this more user friendly for all concerned involves use of a simple Four Step Method which has proven to be very useful.
Properly Established Compliance Applications Provide Valuable Learning Platforms - Dr Donald Glass Engineering Consultant & Executive Director, St James Software - A number of facilities in North America have configured their Compliance Management applications together with other Operations Management applications (such as operations logbook, handover logbook, incident manager, hazard & root cause analysis) to provide a platform for continuous learning about the facility, the operations and the risk areas. An example of this approach can be observed in the linking a permit-to-work application with an operations management operation. The resultant, automatic escalation of high risk situations, combined with relevant information, allows the permit to work application to not only set a high standard - supporting the drive for high safety standards - but simultaneously help employees improve their skills while performing their duties. This paper examines how managers can use compliance programs to help with the training of new staff as well as with the streamlining of maintenance, safety and environmental programmes.
Electrical Safety for Engineers and Supervisors - A First Primer - Gary Triffitt - The purpose of this paper is to ensure that you, the audience, are made aware of the dangers and of modern practice in hazard management with particular reference to electricity.
Fault Reduction Strategy using Neutral Earth Resistor (NER) Installation - Cheng Lee - Lead Engineer, Peracon - Co-author : Frans Cloete, Peracon - Fault level reduction is an ongoing challenge in a growing electrical network. With generation and network capacity continually being added to the system, the fault levels in various locations of a distribution network will soon approach their maximum allowable design level. For electrical power distribution companies there are a number of business drivers that force the implementation of fault level reduction schemes. While the general operation of Neutral Earthing Resistors (NER) for fault level reduction is well understood, optimisation of the design under various network configurations to yield maximum benefit requires detailed study. This paper presents the studies carried out in assessing the impact of Neutral Earthing Impedances of varying sizes for phase-ground faults on a “generic” network with three different configurations: Delta-Star Transformer configuration; Star-Star Transformer configuration; and Bus Tie CB Open (Delta-star Transformer configuration) The impact of Transient Recovery Overvoltage (TRV) on selected zone substation configuration resulting from the installation of NERs is also presented.
Arc Flash
Evaluation of Arc Flash Hazards Using Computer Based Simulation - Hilton Bennie - Senior Electrical Engineer, Applied Energy Solutions (Pty) Ltd - As engineers are responsible for the safety of personnel, it is our responsibility to perform the Arc Flash Hazard Analysis as accurately, yet conservatively, as possible. Being overly conservative may yield unnecessarily strict PPE requirements, which may be cumbersome and ultimately counter-productive. Engineers need to have tools and systems in place to ensure a high level of confidence in the results of the Arc Flash Analysis. We need the ability to perform our analyses on various scenarios, making sure that we account for the worst reasonable case.
Assessment and Selection of Arc Protective Performance of PPE - Go Beyond the Norms - Dr Helmut Eichinger -Technical Marketing Manager, Senior Consultant, DuPont International Operations, Geneva, Switzerland - The arc protective performance of PPE is usually expressed by its arc rating, typically its ATPV, evaluated according to ASTM, IEC or EN standards. Recent developments, findings and discussions suggest that more considerations should be given to further test result parameters (such as EBT, ELIM and/or Box test Class 1 and 2) and also that the understanding of the meaning of the test results with respect to probability of skin burns needs to be improved. Furthermore, there exist important performance assessment and selection aspects, which are not or only insufficiently dealt with in the existing norms, such as robustness of the arc protective performance as a function of laundering, wear conditions, contaminations, or such as wearer acceptance, aesthetics, comfort and heat stress, or whether and how to include underwear in the selection of appropriate arc protective PPE.
Calculating Arc and Incident Energy in an Arc Flash - Where do the Equations come from? - Prof Jerry Walker - Director, Walmet Technologies (Pty) Ltd - This paper gives a brief overview of the first formulas and methods developed since it was first recognised that Arc Flashes play a major role in electrical accidents, to the accepted methods and formulas used in present National and International Standards. It also highlights the deficiencies and constraints in the different methods. The formulas for the calculation of the incidence energy at a specific distance (arc flash boundary) are given but not discussed.
Grounded! - How to Deal with Arcing - Tommy Roes - UDT Business Unit Manager, Martec - Arcing is more common than we would like to believe, even in new installations. Detecting these defects can be challenging, particularly at an early stage. Not one inspection technique, can on its own, detect and localize every defect. Selecting the most appropriate method, requires that inspectors understand the nature of the defect and the signs and signals available to be detected. The next logical step is to have the right technology available to pin point their location. Discover the technologies and inspection techniques that should become mandatory for all electrical maintenance personnel. To not only reduce the risk of arc flash exposure, but also enhance the overall reliability of the electrical system. This paper discusses simple and practical solutions available for reducing Arc Flash related injuries or death, the obvious “front runner” in the “risk” department, and rightly so. Be that as it may, how far down the list do “loss of electrical assets” and “unplanned downtime” sit? The paper looks at a “win win” situation which will reduce the risk of all three.
Arc Flash Protection Study - Eskom Kendal Power Station - Linda Dlamini - Senior Portfolio Manager - TFMC and Moeketsi Melele - Senior Supervisor - Eskom PTM - Major strides have been made in understanding and preventing the undesirable consequences of arc flash incidents in the power utility. Fault level studies using some of the advanced software models, e.g. DigSilent and estimating incident energy and arc flash boundaries with some degree of accuracy using IEEE1584 model, are some of the greatest developments. Controlling exposure to arc flash is the last resort once the means to eliminate, or engineering means to reduce have all proven counterproductive or cost-ineffective. To achieve the right level of control, the solution of PPE has been implemented. This, together with other interventions to limit exposure to electric arc may significantly reduce the risk of exposure. The paper seeks to explain the studies leading to the decisions on Arc Flash PPE.
Development of Standards for MV Switchgear Rated for Arc Protection - Bryan Johnson - Product Group Manager, MV Switchgear, ABB South Africa - Switchgear standards historically considered the electrical capability of switchgear with little regard to the effects of internal arc. To achieve some degree of safety users and manufacturers have considered, measures ranging from PPE, specific operating procedures, through to remote control and arc detection systems, however these measures do not change the characteristics of the switchgear, and therefore the switchgear / switch room should still be considered a high risk area.
Arc Flash Protection - What More Can Be Done? - Laura Steenkamp - What more can be done to mitigate the risks of arc flash related injuries? This paper explores two aspects that already mitigate arc flash risks and poses questions as to why they may be less effective than anticipated. Why do fatalities still occur given the effort placed on proper procedures and clothing during switching? The paper also looks at the term ‘human error’ and what it means for the future of electrical arc safety.
Reducing Risk to Workers Using Infrared Windows - Steve Edwards - R&C Instrumentation - Temperatures can reach as high as 20000°C causing rapid expansion of hot air around the flash area. Copper Busbars vaporize and expand up to 67000times. A piece of copper Busbar the size of a pea becomes the size of a rail car. Molten copper now becomes hot shrapnel. This anomaly is asset destroying, unpredictable and if you are in its path it hurts. So, how can we make this safer? What about keeping the panel closed and doing the thermography through the closed panel? Impossible right? Wrong! A solution is available through the installation of infrared windows, which means the inspection can be carried out efficiently with the energised system enclosed behind a closed door. In fact, the installation of IR windows will not only make the inspection process safer, but will also save cost.
ROI Case Study 2 - Paper Mill Boosts RCM Program with Cost Savings Generated by its IR Window Program - Martin Robinson - Level 3 Thermographer, President & Chief Engineer, IRISS, inc. - A paper mill in Georgia had run a very successful infrared inspection program for a number of years using a local, contract thermographer working with the mill’s in-house electricians. Although the program had a good track record, senior management was concerned about the potential impact of NFPA 70E requirements, and how best to comply with them. The plant commissioned IRISS Inc. to conduct a cost-benefit analysis and present its recommendations.
Arc Flash - Safety by Design in LV Switchgear - David Stonebridge - ABB Australia - The Australian WH&S regulations & codes of practices have undergone dramatic changes in recent years. In 2012 the state & territory governments have to some degree harmonised the WH&S requirements, however when it comes to Arc Flash the debate continues with no firm national harmonised recommendations. Many mining companies in Australia have adopted the US regulations which have also undergone changes when it comes to protecting workers against Arc Flash. The focus of this paper is to look at safety by design in LV switchgear to protect workers against arc flash and to eliminate the need for PPE levels higher than category 2.
Internal Arc Safety in New and Existing Switchgear - Richard Blakeley - RPS SWITCHGEAR LIMITED - This paper highlights the issues in managing elderly oil-filled switchgear and explains the modes and consequences of failure of this equipment. It explains what happens when a ‘flashover’ occurs inside a switchboard and shows how the experiences of designing and testing switchgear to the latest standard for internal arc withstand can be successfully applied to existing switchboards to bring them in line with the latest requirements for internal arc safety.
Electrical Safety from the Ground Up - Proper Grounding and Bonding is Critical for Electrical Workplace Safety - Reza Tajali - Risks associated with shock and electrocutions from inadvertent contact with energized parts have long been recognized as a threat to electrical workers. In recent years, OSHA and industry associations recognized the severity and urgency of the situation which resulted in the development of new standards for electrical workplace safety. In essence, they mandate that work on electrical equipment must be performed in a manner that does not expose the worker to undue risk of injury. While arc flash awareness has been growing (as well it should), the dangers of shock and electrocution should not be overlooked. In fact, electrocution is the second leading cause of construction site fatalities in the US. In an average eight-hour day, 16 workers require time off the job to recover due to electrically induced injuries - from Schneider Electric Engineering Services and Plant Engineering.
Digital Substation
Movement to The Full Digital Substation for Primary Distribution - Albert Massoud - Automation Engineer & Account Manager, Alstom Grid - Digital devices such as numerical protection relays and digital control systems are prevalent in Substations today with a wide range of Technology being utilised. This article looks at other substation areas into which digital technology can permeate, such that progressively, substations can become fully digital in their implementation.
Evaluating Fire and Heat Damaged Electrical Equipment
NEMA Publishes Evaluating Fire- and Heat-Damaged Electrical Equipment - The National Electrical Manufacturers Association (NEMA) recently published Evaluating Fire and Heat-Damaged Electrical Equipment, a guide that provides information on how to evaluate electrical equipment that has been exposed to heat and fire residue through fire, firefighting activities, or close proximity to fire.This guide is useful for suppliers, installers, inspectors, and users of electrical products. Before this publication, little guidance was available for installers and inspectors on how to evaluate electrical equipment that has been exposed to heat and fire residue. Evaluating Fire and Heat-Damaged Electrical Equipment may be downloaded at no cost on the NEMA website.
IEC61850 Based Process Bus Protection Systems
IEC61850 Based Process Bus Protection Solution for Remote Located Power Transformers - Dinesh Mithanthaya - Design Manager, Horizon Power - This paper emphasises the use of an IEC61850 process bus based solution to meet all the protection requirements of transformers. The sensitivity, selectivity, stability, speed and reliability of the scheme can be achieved, by using a single unit protection relay, with the electrical secondary parameters converted to digital data at the switchyard equipment, and transported through fibre link, with no electrical interference or cable burden issues. It is a neat and clean solution, easy to install and maintain, leading to cost benefit to the user.
Power Transformers
An On-Line Technique to Detect Winding Deformation within Power Transformers - A. Abu-Siada - Senior Lecturer, Curtin University - Frequency Response Analysis (FRA) has been growing in popularity in recent times as a tool to detect mechanical deformation within power transformers. To conduct the test, the transformer has to be taken out of service which may cause interruption to the electricity grid. Moreover, because FRA relies on graphical analysis, it calls for an expert person to analyse the results as so far, there is no standard code for FRA interpretation worldwide. In this paper an online technique is introduced to detect the internal faults within a power transformer by considering the voltage-current (V-I) locus diagram as a transformer fingerprint that can be measured every cycle to provide a current state of the transformer. The technique does not call for any special equipment as it uses the existing metering devices attached to any power transformer to monitor the input voltage, output voltage and the input current at the power frequency and hence online monitoring can be realised. Various types of faults have been simulated to assess its impact on the proposed locus. A Matlab code based on digital image processing is developed to calculate any deviation of the V-I locus with respect to the reference one and to identify the type of fault. The proposed technique is easy to implement and automated so that the requirement for expert personnel can be eliminated.
Transmission Power Transformers
Condenser Construction and Awareness of Negative Power Factor on Dielectric Dissipation Factor (DDF) Measurements - Wayne Proud - Technical Officer, Westernpower - As an owner of Transmission High Voltage transformers you will want to manage your plant on condition. One of the accessories of a Transmission Power Transformers is the bushings. A failure of this accessory will lead to a loss of supply from this asset and may even result in a transformer fire which would not only destroy the Transformer, but it may lead to the destruction of neighbouring plant. As an Asset Manager you will have a need to reliably measure the capacitance and Dielectric Dissipation factor (DDF) of the bushings to monitor their condition. As quality control results needs to be accurate and reliable, inconsistencies can lead to poor evaluation and premature replacement. This paper discusses the principals of condenser construction related to testing bushings and presents a case study of the phenomenon of negative results associated with DDF measurements which could influence trending.
Electrical Wiring
Electrical wiring - from Wikipedia, the free encyclopedia.
Electrical and Instrumentation Enclosures
Jump to Subject:- Electrical and Instrumentation Enclosure Design and Specification | Electrical and Instrumentation Cabinet and Enclosure Construction | Fieldbus Enclosures | Electrical and Instrumentation Enclosure Standards | Electrical and Instrumentation Enclosure Cooling | Enclosure Fire Protection | Enclosures for Arctic Conditions | Instrument Enclosures, Sunshades and Supports | Electrical and Instrumentation Enclosure Maintenance
Electrical and Instrumentation Enclosure Design and Specification
Know your Instrument and Electrical Enclosure - This document details some pertinent design requirements for Instrument and Electrical Enclosures.
Typical Instrument and Electrical Enclosure Specification Index - Although you will need to "fill in" all the technical details, this typical index does make sure that most requirements are covered.
Electrical Enclosures - This Typical Standard from CSBP covers the design, manufacture, works testing, supply and on site delivery for the following:
- 415V motor control centre
- 415V switchboards
- 415V lighting and small power distribution boards
- Control panels
- PLC cabinets
Designing for EMC - The main EMC problems for electronic products are the emissions of internally-generated high frequencies which may interfere with on-board or nearby radio reception, and susceptibility to transient or radio frequency interference from the external environment which may degrade the quality of analogue signals, or corrupt digital processes. EMC standards specify levels and test methods for both of these groups of phenomena. A further requirement which comes under the umbrella of the EMC Directive is that the mains supply input current should be limited in its harmonic content. If they are dealt with as an integral part of the product design, these requirements are not hard to meet. Too often, because they do not affect the visible performance of the product, they are not considered until the design is substantially complete and production is about to start. Incorporating EMC principles as an afterthought is expensive and time-consuming. Only 15% of products which have not been designed for EMC are likely to pass EMC testing first time; on average between one and two re-designs (and re-tests) are necessary before such products are certifiable - from (www.elmac.co.uk).
Typical Instrument Enclosure Specification - This document highlights the typical items that need to be considered when specifying an enclosure. From INTERTEC Instrumentation.
Avoid Thermal 'short cuts' to Improve Protection Efficiency - Specifying an enclosure for field-based instrumentation is not a trivial task. If the enclosure is destined for an extreme environment - such as desert or Arctic regions - starting such a configuration process with one of the commonplace styles of metal enclosures used for electrical panel gear is usually not such a good solution, and can pose problems for the inexperienced - from Intertec.
GRP Composites are the Material Of Choice for Tomorrow's Offshore Enclosure Applications - Enclosure designs for protecting offshore equipment are evolving rapidly to combat the widespread problem of corrosion, and to meet industry demands for higher levels of safety and reliability, and new functionality. Among the demands satisfied by enclosures made from GRP (glass reinforced polyester) based composite materials are superb resistance to the corrosive forces of the offshore environment, an ability to make pressurised explosion proof (Ex p) enclosures in any size - not just the small types that are commonly available - as well as the ability to withstand blast forces and jet-fires - from Intertec.
The following links are compliments of Weidmüller:
Hazardous Areas Technical Guide - This excellent 70 page technical guide. This is a large pdf download at 5 Megs, however it is worth the wait!
Enclosures and Cable Glands - This useful technical catalogue from Weidmüller covers the specification and requirements of enclosures which are often used in harsh environments. They remain reliable for many years thanks to the high quality levels, even when exposed to external influences like water, dust, hard impacts, shock, vibration, corrosion, and extreme temperature fluctuations. All components used in potentially explosive atmospheres are subject to strict safety regulations and are checked to the finest detail in terms of their functionality as well as their resistance and resilience against the prevailing environmental conditions. As each enclosure is only as strong as its weakest point, it is ensured that each individual component is of the highest quality and that it will not therefore cause a weak point in the enclosure. This is a large download but jut about provides all the information required for Enclosures and other Accessories.
ATEX Information - ATEX 95, formerly known as ATEX 100a, is aimed at manufacturers. It applies to equipment and protective devices intended for use in potentially explosive atmospheres. Safety and controlling devices for use outside the hazardous area, but essential for the safe operating of equipment inside it are also covered.
Hazardous Areas Poster - A useful poster which details ATEX and Hazardous Area technical information.
Technical Dictionary - This excellent 44 page document includes Certificates, Electrical data including clearance and creepage distances, and Current load curve. It also covers;
Electrical and Instrumentation Cabinet and Enclosure Construction
Electrical Cabinet Construction - Lots of examples and technical information along with some innovative solutions are detailed - from Weidmüller.
Safe Enclosures for Rough Seas - Sturdy Distribution Enclosures Defy the Harsh Environmental Conditions - Details on marine applications enclosures which have a corrosion resistant surface, absolute seal and Ex approval - from Weidmüller.
Fieldbus Enclosures
Fieldbus Enclosures - Enclosures fully assembled and certified for use with Fieldbus Foundation or Profibus PA application requirements.
Electrical and Instrumentation Enclosure Standards
Global Enclosure Standards within the Electrical Industry - Industry standards for electrical enclosures exist to promote safety, encourage design efficiency and define minimum levels of product performance. In the European and North American electrical industries, several standards are enforced for these reasons. Across the global marketplace, these or other standards may be followed or there may be no standards at all, which can lead to wide variations in product performance and price. In many cases, the end customer is not aware of the standards or does not clearly understand them and, therefore, does not insist that suppliers provide products that meet the standards. Focusing solely on low price without fully understanding or requiring industry standards can yield a low initial product cost, but could ultimately lead to high maintenance expenses, component failure and in the worst case, worker safety issues. The purpose of this paper is to: (a) Clearly define the industry standards that exist for electrical enclosures (b) Compare the most commonly used standards so enclosure users can understand the key differences (c) Equip decision makers with the knowledge needed to select an electrical enclosure that has the appropriate rating and price to value relationship for its intended application - from Hoffman.
Standards for Enclosures - A useful technical note from Omega.com.
New Standard 61439 for Switch and Control Gear - Compliant Switchgear and Controlgear will supersede the previous standard IEC 60439 from November 2014 - from Rittal.
Electrical and Instrumentation Enclosure Cooling
Cooling System Options for Electronic Enclosure Cooling: Do Thermoelectric Air Conditioners Have the Advantage? - This white paper discusses four popular options for cooling electronic/electrical equipment housed in enclosures and cabinets. These options include thermoelectric air conditioners, compressor-based air conditioners, vortex coolers and air-to-air heat exchangers (heat pipes). Each cooling method is explained and the advantages of thermoelectric air conditioners are examined as compared to the other cooling methods - from EIC Solutions Inc.
Cooling Oil Drilling Electronics in Class 1, Division 2 Environments - Details on a cost-effective air conditioning solution for enclosures to be used to protect electronics in drilling rig equipment - from EIC Solutions Inc.
Instrument Protection Shelter Employs Passive Cooling to Meet Challenges of Middle East Gas Project - One of the largest passively-cooled instrumentation shelters ever constructed is being supplied by Intertec to house remote control and instrumentation equipment required for a new natural gas collection project in the Middle East. Without any electricity, the cooling system reduces interior shelter temperatures by some 20 degrees Celsius - to enable the instrumentation to operate at its desert location - from Intertec.
Passively-Cooled Cabinets Protect Sample Conditioning and Process Analyzer Instrumentation on World’s Largest Vessel - Much of the on-line process analysis instrumentation on the Prelude FLNG vessel will be housed in purpose-built environmental protection cabinets. The cabinets are required to be capable of withstanding severe Category 5 tropical cyclones with wind speeds in excess of 252 km/h (157 mph) and to have a minimum service life of 25 years - with 50 years as a design aim. Additional requirements include a high degree of resistance to corrosion being caused by the saline environment and the presence of sour or acid gas, and the ability to cool electronics equipment without using explosion-proof air conditioning systems, which incur high capital and operating costs - from Intertec.
Enclosure Fire Protection
Enclosure Passive Fire Protection
Innovative Passive Fire Protection Cabinets Extend Margin of Safety for Critical Plant Shutdown Equipment - The cabinets ensure that equipment such as emergency shutdown valves remain operational by keeping them below 60 degrees Centigrade for periods of up to 64 minutes in the event of a hydrocarbon-based fire, to allow time for controlled shutdown - from Intertek.
Novel Passive Fire Shelters Enhance Safety Management for Offshore Gas Project - Fabricated using lightweight composite GRP (glass reinforced polyester) materials, these shelters employ patented techniques to resist fire for two hours - allowing critical electronic safety equipment to remain operational. Although there are currently no standards for this application area that cover containment temperatures, Intertec designs, manufactures and tests its fire shelters to a rigorous proprietary specification which demands that their internal temperature must remain below 60 degrees C throughout the rated protection time. The novel shelters are also capable of withstanding both conventional and more severe hydrocarbon fires - from Intertek.
Unique Passive Fire Shelter Technology Provides New Protection Choice for Process Plant Designers - Includes shelters for hydrocarbon fires with 90-minute protection which are light, corrosion proof, maintenance-free construction and ideal for offshore applications. They are designed to protect critical safety equipment from exposure to high temperature fires in hazardous areas. The shelters are entirely passive, maintenance-free and impervious to a wide range of corrosive chemicals - including salt, sulphur dioxide and sour or acid gas - from Intertek.
Enclosures Protected by Gaseous Fire Fighting Systems
Guidance on the Pressure Relief and Post Discharge Venting of Enclosures Protected by Gaseous Fire Fighting Systems - This document provides guidance on fulfilling the requirements contained in BS EN15004-1 and BS 5306-4, in respect to over and under pressurisation venting - clauses 7.4.1 and 10.3.3. respectively and post discharge extract - clauses 5.3 h) and 15.9 respectively. It considers the design, selection and installation of vents to safeguard the structural integrity of enclosures protected by fixed gaseous fire fighting systems and the post discharge venting provisions where used - from the FIA.
Clean Agent Enclosure Design for ISO 14520 & AS4212 - Clean agent fire suppression systems are required in enclosures where a sprinkler system would cause damage to sensitive contents such as computer servers or historical artefacts. Upon fire detection the compressed agent, which can be a halocarbon or an inert gas, is released into the enclosure causing a peak pressure of around 250 to 1250 Pascals to occur for a fraction of a second, the magnitude of which is dependent upon total enclosure leakage area. Once the enclosure is completely flooded, the agent will begin to leak out at a rate that primarily dependent upon lower enclosure leakage area. The distribution of the remaining agent will either be constant throughout the enclosure due to continual mixing or will establish an interface with air above and agent below an interface that descends in time. Up until 1988, enclosures protected by Clean Agents used full discharge tests to determine the Hold Time but since 1988, Door Fans have been used for measuring the leakage area which is entered into formulae in Annex E of ISO 14520 to predict how long the agent will stay in the enclosure (Hold Time) - from Fire Protection Technologies.
Enclosures for Arctic Conditions
Outdoor Equipment Enclosures Simplify Instrumentation Installations in Ultra-Cold Environments - These enclosures provide a versatile alternative to free-standing cabinets for the environmental protection of field-based process instrumentation. Developed at the request of a Russian oil refinery, the enclosures are made from tough glass reinforced polyester (GRP) and include highly insulated options for use in extremely cold climates. They also offer more space than typical instrument enclosures, to allow plant personnel to use gloved hands when accessing the equipment. Typical applications include housing differential pressure flowmeters and process transmitters in refineries, petrochemical and chemical processing plants - from Intertek.
Instrument Enclosures, Sunshades and Supports
It is essential that Instrument Enclosures and Sunshades are considered where Instruments are subjected to a wide range of environmental factors which might impair the efficiency and operation of process instrumentation, such as extremes of temperature, the ingress of dirt, dust and moisture, corrosion, accidental damage and tampering. Options can include electrical or steam heating, ventilation or integral insulation for protection from the world’s climactic extremes, such as Siberia, where the temperature can fall as low as -76°F (-60°C), or Australia / Middle East, where it can reach in excess of 104°F (+40°C).
Enclosure systems are typically used to protect process instrument manifolds and transmitters, solenoid valves, general field instrumentation and remote chemical sealed instruments.
These types of enclosures can be used with a specific range of enclosure manifold systems which enable ease of instrument installation and provides external process and vent connections.
Instrument Enclosures, Sunshades and Supports - Maintaining the integrity of process measurement instrumentation, protection from the effects of the industrial and the natural environment, both on and offshore, is vital, this technical bulletin from Anderson and Greenwood and Prochem Pipeline Products gives a good technical overview of what is required. The bulletin covers Purpose and Applications, Features and Benefits, Technical Specifications Enclosures, EM Manifold Needle Valve, EM Manifolds, Electrical Heating, Electrical Heating, Enclosure Mounting and Instrument Shades.
Electrical and Instrumentation Enclosure Maintenance
Enclosure Maintenance - David Crooks - Installed enclosures require periodic maintenance. The more hostile the environment, the greater the frequency of maintenance needed, and if done with vigilance, the greater the reward. Vibration, shock, or thermal expansion/contraction may loosen enclosure parts and fasteners. Constant flexing of conduit connections and stresses on liquid tight hubs may erode rubber fittings and seals. Routine inspections and periodic tightening of fasteners can prevent minor annoyances growing into major problems - from Fibox Enclosures.
Standard for an Electrical Preventive Maintenance (EPM) Program - The purpose of this standard is to provide recommended practices and frequencies that would form the core of a regularly scheduled electrical preventive maintenance program. There is a useful section on maintenance of enclosures - from Hartford Steam Boiler.
Know Your Instrument and Electrical Enclosures
Jump to Subject:- U.S. Electrical Enclosure Standards | Electrical and Instrumentation Enclosure Types | IEC Standards for Electrical and Instrumentation Enclosures | Electrical and Instrumentation Enclosure Design Tips | Basic Conditions for Various Electrical and Instrumentation Enclosure Types | Type / Degree of Protection for Electrical and Instrument Enclosures | Electrical / Instrument Enclosures - Cross Reference of NEMA Type Numbers to IP Classifications |
Please note that the original author that this document is based on is unknown. It is ICEweb's intent to fully acknowledge authors. If you are the author please contact
Be "environmentally friendly" to your equipment's electrical components - specify the correct enclosure type.
All electrical equipment enclosures are designed to provide protection against accidental contact with the enclosed equipment and emission of sparks or flame from failure of internal components. In addition, enclosures provide varying degrees of protection against the external environment. Approval of electrical equipment enclosures for the environment is a requirement of the National Electrical Code and critical to the long-term performance of hvacr equipment.
U.S. Electrical Enclosure Standards
Industry standards for electrical enclosures in the United States are published by the National Electrical Manufacturer's Association (NEMA) and Underwriter's Laboratories (UL). The following reference standards should be included in specifications for equipment that include control panels or motor starters: NEMA 250 - Enclosures for Electrical Equipment (1,000 Volts Maximum); UL 50 - Enclosures for Electrical Equipment; and UL 508 - Industrial Control Equipment.
These standards establish basic construction requirements as well as test methods. They define the degree of environmental protection according to a type number common to all U.S. manufacturers.
Electrical and Instrumentation Enclosure Types
Although the detailed definitions of protection afforded by a particular enclosure type may differ slightly between the NEMA and UL standards
Not all enclosure types are available from any given manufacturer, so review the options offered and choose the type that meets or exceeds the requirements of the application. A higher degree of performance generally means higher cost, so avoid the temptation to over-specify. See http://www.iceweb.com.au/Technical/IPNEMA.htm for details of NEMA protection definitions.
Type 2, Type 6 and Type 13 enclosures are limited to special applications.
IEC Standards for Electrical and Instrumentation Enclosures
Enclosures manufactured in Europe must meet the standards of the International Electrotechnical Commission (IEC). They are classified by the letters IP and two characteristic numerals; the first (0-6) identifies the degree of protection against solid objects, including dust, and the second (0-8) the degree of protection against water.
The number of different enclosure classifications possible (48) under the IEC standard is much greater than the number under the NEMA and UL standards. IEC standards tend to allow more application-specific designs, while U.S. standards cover a broad range of applications with a fewer number of ratings. One manufacturer offers a cross-reference of NEMA Type numbers to IP classifications (Table 2).
Electrical and Instrumentation Enclosure Design Tips - As Always - Coordinate
Coordinate the enclosure types you specify for equipment with the electrical designer. Chances are, they are placing electrical equipment in the same spaces as other equipment and have addressed the enclosure requirements. Many electrical construction specifications include a general section defining area classifications and enclosure types that you can reference in your specifications.
None of the above information applies to locations where flammable or explosive liquids, gases, fibers, or dusts are present. Enclosures for these areas must comply with more stringent requirements and be approved for the type and ignition characteristics of the hazardous substance. Seek direction from an electrical engineer qualified in hazardous location design for equipment requirements.
Basic Conditions for Various Electrical and Instrumentation Enclosure Types
Type Location
1 Indoor
2 Indoor
3 Outdoor
3R Outdoor
4 Indoor/Outdoor
4X Indoor/Outdoor
6 Outdoor
12 Indoor
13 Indoor
Type / Degree of Protection for Electrical and Instrument Enclosures
1 Accidental contact only - No environmental protection
2 Falling water or dirt
3 Dust, rain, sleet, ice
3R Rain, sleet, ice
4 Dust, dripping, falling and hose-directed water
4X Dust, dripping, falling and hose-directed water, corrosion
6 Submersible (occasional and temporary, limited depth)
12 Dust, dripping and falling non-corrosive liquids
13 Dust, dripping, falling and spraying non-corrosive liquids
Electrical / Instrument Enclosures - Cross Reference of NEMA Type Numbers to IP Classifications Approximate IEC/IP NEMA/UL Type Classification
1 IP 23
2 IP 30
3 IP 64
3R IP 32
4 IP 66
4X IP 66
6 IP 67
12 IP 55
13 IP 65
Motor Control Centres (MCCs)
Guidelines For Performing Infrared Inspections Of Motor Control Centers - Josh L. White - Understanding the thermal patterns of this equipment is critical to a successful inspection. Also correctly identifying the source of the anomaly can make recommendations more valuable. From ezinearticles.com.
Specification for Motor Control Centers 600 Volts and Below - This specification covers low voltage motor control centers with combination starter units. From GE Industrial.
How to Specify the Right Motor Control Center For the Job - Patrick Daley - When purchasing a new or replacement MCC be sure to address a few important items in your specification. From ecmweb.com and Devon Engineering.
Motor Control Centers Technical Overview - A useful overview from Siemens.
Minimizing Arc Flash Exposure in Industrial Applications - This white paper will discuss the definition of an arc flash, including its risks, consequences and causes, industry standards to protect against arc flash and a solution to minimize arc flash exposure - from Turck.
ICS 1 Industrial Control and Systems: General Requirements - This National Electrical Manufacturers Association (NEMA) publication is available via free download, you need to register.
Intelligent Motor Control Centres
Integrated, Intelligent Motor Control Centres - Motor control centers (MCCs) occupy a prominent role in control schemes, housing a comprehensive array of control and monitoringdevices. MCCs have moved rapidly to include the latest component technologies and integrating these advanced technologies presents a major opportunity - to transform islands of data into useful information that minimizes downtime. This paper focuses on technology integration methods in MCCs, and quantifying associated costs and benefits. From Rockwell.
Intelligent Motor Control - Using Intelligent Motor Control Centers ... Intelligently - Lately, interest in intelligent motor control centers (IMCCs) has increased significantly. But what is an intelligent MCC? To answer the question of intelligence, and to gain insight into the future of IMCCs, we must first take a look back at traditional MCC technology. From Square D.
Optimizing Energy Consumption and Improving Operational Efficiency through the use of Smart MCCs in Process Automation System - The escalating price of fossil fuels marked by fierce global competition is driving process industry decision makers to rethink the way their businesses will perform in the future. In order to stay competitive, manufacturers will have to develop strategies to conserve energy and limit their usage of depleting fossil fuel reserves. However, the challenge in achieving this goal is to do so without disrupting production. This is where the integration of Smart Motor Controls (MCCs) into a process automation system can play a vital role in your energy conservation strategy. From Siemens.
Motor Control Center data offers Maintenance Insight - Terry Schiazza and Anthony Propes - One piece of equipment that is increasingly being incorporated into a plant’s network is the motor control center. An MCC is a safe, economical and convenient way to mount control, distribution and automation equipment in one central location. It typically contains components such as motor starters, drives, circuit protection devices (circuit breakers, motor circuit protectors or fuses), circuit monitors and overload relays. In a networked - or intelligent - MCCs, the plant’s protocol is built into its individual components via hardware, allowing for myriad information from those components and the processes they control to be fed back to plant personnel or even the process itself. Thanks to plantengineering.com.
Checklist for implementing a Smart MCC - This six-step checklist provides the essential steps to implementing a "smart" MCC. From Siemens and chemicalprocessing.com.
Smart MCCs as a Motor Maintenance Tool - This paper discusses the application of Smart MCC technology to standard and predictive maintenance practices used to maximize motor life and help limit unplanned motor failure. An overview and definition of standard maintenance practices is followed by a description of information available from a Smart MCC and how this information can be used. Siemens Energy & Automation, Inc.
Thermal Imaging
Thermal Imaging Electrical Maintenance Application - Efficiently identify electrical issues - Tony Shockey - Today’s thermal imagers are rugged, easy to use, and much more affordable than they were even just a few years ago. They have become a realistic solution for everyday electrical maintenance. To use, a qualified technician or electrician points the thermal imager at the equipment in question and scans the immediate area, looking for unexpected hot spots. The imager produces a live image of the heat emitted from the equipment, and with a quick squeeze of the trigger, captures a thermal image. When the inspection is complete, the technician can upload the images to a computer, smartphone, or tablet computer for closer analysis, reporting, and future trending - from the ISA and InTech.
Programable Electronic Controller (PLC)
The following technical information is From Automation Direct.com
Considerations for Choosing a PLC
A Condensed Guide to Automation Control System Specification, Design and Installation - T. Elavsky - Automation Direct
Connecting 3-wire sinking and sourcing devices to PLC input modules
Relays Show Staying Power: As Their Control Capabilities Increase, Relays Encroach on PLCs - Jim McConahay contributes to this article outlining advantages of relays and programmable relays over PLCs. Relays have many electrical and safety advantages over PLCs, and programmable relays can outshine PLCs in real-time control and monitoring. From Moore Industries-Pacific, Inc. and Control Design.
Automating Manufacturing Systems with PLCs- This is a sensational 846 page book full of information on PLCs, logic design, Sensors etc - from Grand Valley State University and written by Hugh Jack- A 5.4Mbit download but worth the wait!
PLCs - Terminology,Tools, Tables and Calculator s- From Controlsweekly.com.
PLC Glossary of Terms - A complete glossary of the most often used terms in PLC systems - from www.industrialtext.com.
PLC Primer - A very useful 16 page document from www.industrialtext.com with all the basics about PLCs.
PLC Basics - A fantastic 39 page tutorial and associated exam from Eaton Electrical.
PLC Resource - Lots of great technical papers and tools here - From PLC Open.
Your Personal PLC Tutor Site - From PLCs.net.
PLC Basics - From the PLC Man.
Basics of PLCs - A tutorial from Siemens.
Primer on Programmable Controllers - Thomas A. Hughes - A useful introduction to PLCs which details basic components, I/O System & Structure along with Input & Output Types - from ISA and InTech.
Troubleshooting the Workhorse of Engineering Industry - the PLC - Steve Mackay - One of the workhorses in industry - no matter whether you are in industrial automation, electrical or mechanical engineering, you are likely to be confronted with one of these little fellahs - a Programmable Logic Controller or PLC (or indeed, Programmable Automation Controller - PAC). A critical cheap building block for all automated systems. Effectively, an industrially hardened digital electronic device in which a sequence of instructions are stored, which enable the PLC to replace hard wired relay logic and perform counting, sequencing and timing. As well, as reading analog inputs (e.g. from a flow meter) and outputting analog output control signals to valves and other control devices. A few tips on troubleshooting these devices are detailed in this blog (yes - the veterans amongst you will sigh, when you know your enormous depth of experience built up to do this - as against my short note below). I have presumed in the suggestions on troubleshooting, that your PLC has been operating correctly and there are no recent program changes.
Electrical and Instrument Wiring Terminal Connections
The following is from Weidmüller Pty Ltd
Modular terminals are available with many different types of connection - The principles of some of these are detailed below;
Spring Connection
The Weidmüller tension clamp system functions in a similar way to the proven clamping yoke. Separation between the mechanical and electrical functions has also been maintained with the tension spring version. The tension clamp made of high-quality, non-rusting and acid-resistant steel draws the conductor towards the electroplated copper current bar. Minimal contact resistance and high corrosion resistance is achieved by the tinlead plated surface and permanently maintained by the compensating action of the tension clamp. |
Solder Connection
The solder connection is still important in certain areas of electrical engineering. Conductors up to max. 2.5 mm 2 are directly soldered to solder lugs or solder brakets. Soldering guarantees a good electrical connection, the prerequisite being that this work is correctly performed. |
Spring-clip connection
The spring-clip connection is a solderless electrical connection (DIN 41611, Part 4). The connection is chieved by a pneuma-tic gun. The spring-clip and the conductor are simultaneously shot onto a pin with rectangular or square cross-section. The method is suitable for both solid and stranded conductors up to max. 0.5 mm² (AWG 20). The tool (gun) and spring-clips are available from AMP Deutschland, D-63225 Langen. |
Pressure Clamp Connection
With the patented pressure clamp connection system, Weidmüller has developed a screw connection system for large conductors. The often difficult insertion of large conductors into the clamp is facilitated by easy removal of the crew unit form the terminal. The conductor is then placed directly on the current bar, the screw unit inserted and the conductor clamped tight. |
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Principle of vibration resistance
On account of the difference in length d between the shank of the clamping screw and the resilient pressure clamp, the pressure clamp deforms elestically when the screw is tightened. The high spring force of the pressure clamp produces the vibration resistance and compensates for any movement of the connected conductor. Retightening of the clamping screw is, therefore, unnecessary. |
Top Connection
The TOP connection system from Weidmüller fulfils the requirement that insertion of the conductor and actuation of the screw occur in one direction. This brings wiring advantages under certain assembly conditions, e.g. with small lateral spacing in component containers. The TOP connection system combines the special properties of steel and copper. The conductor is pressed directly against the copper of brass current bar by a hardened steel pressure yoke. The high contact force guarantees a gastight connection between conductor and |
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Principle of vibration resistance The force exerted by the steel pressure clamp when the screw is tightened pulls the two halves of the TOP connection apart, as with the clamping yoke. This exerts a locking action on the screw and provides excellent vibration resistance. |
Surge and Lightning Protection
It will never happen to me? Don't you believe it ... Globally, some 2000 on-going thunderstorms cause about 100 lightning strikes to earth each second!! |
Modern day industrial facilities contain large amounts of microprocessor based equipment from control computers to field sensors. High speed data is transferred around a site to allow business decisions to be made which affect productivity and efficiency. The real time data used for such control and decision making would be useless if corrupt and, worse still, the complete loss of such a system due to surges or lightning would impact on productivity and profits.
Much of the industrial equipment is installed in harsh environments, subject to natural disturbances such as lightning and man made disturbances like switching transients from motors, pumps, welding equipment and variable frequency drives. Small transients and disturbances on the ac or data cables, whilst not causing catastrophic damage, will be slowly stressing the internal microprocessors ultimately leading to degradation which manifests itself as errors or complete failure.
A direct lightning strike can be catastrophic and cause safety related failures and potentially plant shutdowns. The lightning does not have to strike directly even, a nearby strike within a few kilometres can be extremely damaging causing minor failures and potentially stressing control or system hardware.
Surge protection for these industrial process applications can prevent the majority of upsets caused by surges and transients. It is essential as part of the plant infrastructure and can prevent downtime and lost productivity. In all areas reliability will be enhanced increasing availability and uptime. Telematic and Atlantic Scientific have been at the forefront of industrial surge protection for the past 15 years and have the product to protect your facility.
Technical Links From Around The World
4.13 The following links are from IDC Technologies.
Lightning Protection
Protection against Lightning Physical Damage and Life Hazard - SANS 10313:2010 & IEC 62305 Part 2 & 3 Explained - T.J. Manas - This paper covers the process of assessing the risk of damage caused by lightning and give an in depth description of the requirements of protecting structures and living beings against the hazards of lightning - from IDC.
Lightning Protection for Equipment on MV feeders - WJD van Schalkwyk and M. du Preez - This paper presents the influence of lighting on MV feeders supplying small power users (400/230V). Attention is given to insulation failures leading to poor power quality. In order to minimize power interruptions, lightning related trips are reduced mainly by minimizing MV equipment failure. Examples of arc quenching are also studied.
Lightning Protection of Rail and Related Industries - AM (Bert) Hanekom - The rail environment is challenging and merciless. The overhead traction structure literally forms a huge lightning antenna. This requires a systems thinking approach to protect elements that are rail bound, rail mounted or in close proximity to the track, against lightning surges. What makes things even more challenging is the rapid growth in the use of low powered electronic devices in the rail environment. For example, signaling installations have evolved from mechanical interlockings to being based on sophisticated electronic sub elements. Additionally, condition monitoring of the rail infrastructure has brought in numerous electronic systems. Hence the critical need for lightning protection in all aspects of the rail network. The author’s real experience in lighting protection of rail systems is shared with you.
Lightning Protection for Industrial Plants - Phillip Tompson - This paper provides an outline of a systematic approach to determine and apply lightning and surge protection to industrial plants such as water and sewerage and oil and gas facilities. All too often when lightning strikes an industrial plant, equipment is damaged and operations curtailed there is an initial rush to get the plant operational again. This is a reasonable response. Then comes the question of how to protect the plant against the next lightning strike. Inevitably the approach taken is ad hoc and the result is very often a lightning protection system that does nothing to protect the equipment that was originally damaged. Indeed by taking a systematic approach, applying the Australian standard, carrying out a risk assessment, then acting upon the results of that risk assessment both cost effective and successful solutions can be found.
Surge Protection
The Need to Ensure Energy Co-ordination of Surge Arresters in terms of SANS 10142:2009 section L.1.3.3 - Paul van As - This is a topic which is regularly overlooked and probably the most common cause for failure of surge arresters. Many people believe that the more surge arresters you install the better the level of protection obtained. This is all very well if viewed purely from a voltage protection perspective but can lead to premature failure of surge arresters. Cascading of surge arresters based purely on voltage protection levels without fully understanding energy co-ordination is a recipe for disaster. Many suppliers of surge arresters tend to sell their products purely on surge handling ability (kA), reaction time and clamping voltage. Obviously the surge arrester that reacts the fastest is the first to operate and hence takes most of the energy. In many cases this can lead to low energy, fast reacting surge arresters being overstressed causing damage to equipment. In light of the above problem SANS 10142-1:2009 section L.1.3.3, which states “When more than one SPD is connected on the same conductor, coordination between them shall be ensured.” Many manufacturers and sellers of surge arresters have no idea as to how their surge arresters will react when cascaded with each other. This problem is further aggravated when different surge arresters from different manufactures are installed in an installation.
Accurae Soil Resistivity Testing for Power System Earthing - Rodney Urban, Karl Mardira - Soil resistivity data is of fundamental importance in performing earthing system analysis. Reliable data is required to achieve good correlation between design and measured earthing system performance. The findings of numerous soil resistivity tests in the Sydney area for rail system earthing design is presented in this paper. The installations were inside the rail corridor where testing was often very restricted or not possible due to hazards, space limitations and adjacent buried metallic services or structures. A comparison of the results indicates the possible variation of soil resistivity at various depths over small distances and how this can be accommodated in the design process.
Arrester Earthing Resistance - Tony Gillespie - An analysis of the earthing resistance for surge arresters on the distribution network. The simplified analysis is based on lumped parameter circuit impedance values for a lightning strike.
Power System Earthing Due Diligence - Gaye E Francis and Richard M Robinson - There have been two primary paradigms of safety risk management co-existing uneasily over the last few decades. One is related to hazard based risk analysis driven by technical professionals using target levels of risk and/or safety. The other is the precaution based risk analysis driven by the courts focusing on ‘due diligence’ being a demonstration that all reasonable practical precautions are in place based on the balance of the significance of the risk vs the effort required to reduce it. The publication of the EG-0, Power System Earthing Guide, Part 1: Management Principles by Energy Networks Australia in May 2010 supports the hazard based / risk target approach to risk management whilst the impending (2011) national Model Workplace Health and Safety Act requires a positive duty of care for responsible officers to exercise ‘due diligence’. This paper will investigate the underlying conflict between the two positions and the manner of expected resolution using EG-0 as the focus.
Effective Surge Protection Installation - Phillip Tompson - Managing Director, Novaris Pty Ltd - This paper provides an outline of how to effectively install surge protection to various elements of an industrial plant. The paper highlights the need to consider cable impedance and the importance of equipotential bonding.
Comparison of Different Class I Surge Protective Devices for the Protection of Mobile Phone Stations - Holger Heckler, John Ortika - Phoenix Contact (Germany & Australia) - IEC Class I surge protective devices (SPDs) - for the diversion of direct light-ning currents - are frequently used for the protection of low-voltage AC power systems. Nowadays more and more telecommunication applications are also powered with DC power systems (An example being radio base stations, which are equipped with Remote Radio Heads or Remote Radio Units {RRH/RRU}). Remote radio heads are usually powered with 48 V DC. For the efficient protection against the effects of direct lightning strikes, remote radio heads have to be protected with surge protective devices which are suitable for the installation in DC power systems. The IEC standards which describe the requirements and the test conditions for surge protective devices (IEC 61643-1, IEC 61643-11) do not address SPDs connected to DC power systems. In this paper special requirements for SPDs, connected to 48 V DC power systems, are defined and described. Tests carried out with different high performance Class I lightning current arresters, connected to a newly designed test circuit, show the advantages and restrictions of the use of these arresters in DC power systems. The tests had been carried out with different kind of spark gaps, varistors and combinations of spark gaps and varistors.
Practical Insulation Co-ordination for Lightning Induced Overvoltages - Jason Mayer - Technical Director, Energy Services, Aurecon - This paper provides guidance on how to undertake insulation co-ordination simulations in high voltage systems, using time domain software. There are a number of methods used in industry to complete this task. Some are simplified approximations, others involve statistical analysis. This is just one method, but it is a practical means of assessing the level of protection afforded by surge arresters in high voltage systems, against lightning strokes to exposed conductors. The paper does not consider overvoltages from switching transients or other sources, although some of the principles presented could be used in this area.
How Real Time Lightning Data Improves Safety & Reduces Downtime - Ken Ticehurst - Managing Director, Kattron Lightning & Weather Data - A lightning wide area detection network, part of Earth Networks global Total Lightning Network (KENTLN), provides a significant detection advance which enables the severity of a storm to be determined by the rate of Inter-Cloud flashes, 21st century technology provides advanced storm severity before damaging ground strokes begin. Advanced warning can provide alerts 30 to 45 minutes ahead of older technology
Lightning and Underground Mines - An Introduction - Franco D’Alessandro - Principal Consultant, PhysElec Solutions Pty Ltd - Effective mitigation of direct and indirect lightning discharges is an important aspect of the reliable operation of any mining operation. Whilst a systematic protection plan can be implemented relatively easily for above-ground operations, the circumstances are rather more complex for underground mines. The counterintuitive nature of assessing the risk lightning poses to underground mining operations will be developed in this paper. It commences with an overview of the key characteristics of lightning and then outlines the main variables and transfer mechanisms of relevance to underground mines. The paper then provides some examples of calculations carried out to quantify the dangers lightning poses underground.
Other Links
Remote Location Power Surge Protection - David Torres - Remote sites include locations such as telecommunications shelters, cellular towers, water/wastewater treatment plants, railroad bungalows, and HVAC systems. These installations can be challenging to protect from lightning, line surges originating from utility switching, damage to power utility lines, and power surges originating from area industrial equipment. Devices in remote locations are typically closer to the service entrance and lack other power paths for energy to flow. This makes them more susceptible to surge damage than other applications. When planning a remote installation, the design engineer or installer must consider proper grounding and bonding, the correct surge protection device (SPD) for the job, and proper installation. When installed correctly, it is possible to protect a remote site from lightning or other surge events - from ISA and InTech.
Lightning Protection System - Ultimate Line of Defense - Mark S. Harger - Lightning, one of nature’s most destructive forces, continues to wreak havoc on lives and property especially in today’s electronic environment. On average, a lightning strike contains approximately 50 million volts carrying 18,000-20,000 amperes of current, but strikes with up to 300 million volts and 200,000 amps are not that uncommon. To protect against this destructive phenomena, a properly designed and UL-listed lightning protection system is required. The National Fire Protection Association (NFPA) 780 Standard for the Installation of Lightning Protection Systems defines a lightning protection system as “a complete system of strike termination devices, conductors, grounding electrodes, interconnecting conductors, surge suppression devices and other connectors or fittings [that] are required to complete the system.” How does this system work? Picture a hockey goalie protecting his net. He has four basic tools—gloves, mask, stick, and pads—that help him prevent the puck from entering the net. Just like a goalie, there are four main parts that comprise a lightning protection system - from Nema.
Proper Copper Grounding Systems Stops Lightning Damage at Nebraska FM Station - What could be more vulnerable to lightning than a 500-ft antenna tower poking into the Nebraska sky on a summer afternoon? And what could be more at risk from serious lightning damage than the sensitive electronic equipment in a radio station’s transmitter room? One station knows these hazards all too well. KROA, a 100-kW FM station with studios and tower in Doniphan, Nebraska, learned first-hand what happens when lightning strikes and where the lightning goes if the tower it strikes is connected to high-resistance ground. From Copper.org.
Preventing Direct Lightening Strikes - Roy B. Carpenter, Jr - This paper looks at lightening strikes and how to prevent them - from lecglobal.com.
Lightning and Static Effects on Industrial Electronics - This data sheet from Emerson Process Management examines the damage caused by transients from lightning and static and offers advice on minimising the harmful effects of these two phenomena.
Designing for Surge Immunity In International Markets (Applied Energy Concepts - www.aeconcepts.com).
Surge Protection for Modern Process Control and Automation Technology - (Dehn USA - www.dehn-usa.com/).
Lightning Protection for Dam Instrumentation - A paper by Anthony Moulds and Anthony Watson, thanks to http://www.slopeindicator.com/.
Application of Surge Protection Devices for Very Low Voltage Devices - Mike Green - thanks to Megavolt (http://www.megavolt.co.il/) - This paper offers a three point method for simplifying the Surge Protection Device (SPD) selection process, while pointing out the necessity for studying the application in its entirety.
Surge Protection of End-User Equipment - François D. Martzloff - National Institute of Standards and Technology - Technically valid and cost-effective surge protection of end-user equipment can only be achieved by matching the surge withstand capability of equipment (with or without added protection) to the surge environment, the latter being generally beyond the control of the end-user. Thus, three sets of questions must be answered by a facility engineer to arrive at a reliable approach, this paper discusses these.
Surges Happen - How to protect the appliances in your home - A 24 page document from the National Institute of Standards and Technology
NFPA-780 Standard for the Installation of Lightning Protection Systems (1997): Transitioning From An Outdated Concept to Approved Alternatives - By Richard Kithil, President & CEO, NLSI.
Proper Copper Grounding Systems Stops Lightning Damage at Nebraska FM Station
Safety, Power Quality, Communications Improve with Low-Resistance Copper Grounding System - thanks to the Copper Development.
What You Should Know About Lightning Protection - By Joseph H. Reisert - from Astron Wireless Technologies.
Lightning Protection - New Myths & Old Realities As They Apply To Your Home And Your Station - by Bob McGraw - K4TAX.
Lightning Protection of weighing systems - From revere transducers- Europe (www.revere.nl).
Coordination of Telecommunications Surge Protective Devices in Countries with Unstable AC Power - Peter Nystrom-Applied Energy Concepts, Inc. (www.aeconcepts.com).
Lightning Links - from the university of Florida Vladimir A. Rakov, Ph.D. Professor) (http://plaza.ufl.edu/rakov/).
Public Interest Energy Reseach OTC Report on Light Activated Surge Protection Thyristor (LASPT) - 74 pages here - ADSL recommended - From the California Energy Commission - www.energy.ca.gov - The electricity system in California is vulnerable to large-scale power disruptions due to rapid power surges resulting from lightning or mechanical failures. These rapid surges cannot be fully mitigated by the existing surge protection devices in power plants and the transmission and distribution systems. The economical cost of these power failures amounts to more than $1 billion dollars a year. The overall goal of this project was to develop a surge protection device with a response with an order of magnitude faster that systems currently used by the electric power industry. Many current surge protectors employ a switch known as a thyristor that is activated by electrical current. Our goal was to develop a prototype of a Light Activated Surge Protection Thyristor (LASPT) that would respond much faster than current activated thyristors.
Lightning Protection for Wind Turbines - The Lightning Protection Project was conceived by the National Renewable Energy Laboratory (NREL) to improve the understanding of lightning caused damage to wind turbines and how to protect them. This project report is very comprehensive thanks to www.solacity.com.
A New Lightning Protection System for Wind Turbines Using Two Ring-Shaped Electrodes - Yasuda Yoh - This technical paper focuses on a method for protection of low-voltage and control circuits in a wind tower, detailing a new lightning protection system with two ring-shaped electrodes attached to the wind turbine.
Lightning Protection in Rocket Design - Bruce C. Gabrielson Aerojet Electrosystems Azusa, California
The following Surge and lightning protection Application notes are from MTL Instruments
Lightning Surge Protection for Electronic Equipment - A Practical Guide - This publication discusses the nature of the threat to electronic instrumentation and communications networks posed by voltage surges induced by lightning or other causes, and describes the practical application of surge protection devices (SPDs) designed to prevent damage from such sources.
Lightning and Surge protection - Basic Principles - This publication discusses the mechanism of lightning and the design of surge protection devices (SPDs). The criteria for choosing the most suitable models for a wide range of applications in process industries are established. SPD applications for computers, networks, telecomms and various building systems are discussed.
Earthing Guide for Surge Protection - This publication discusses the major aspects of earthing surge protection devices (SPDs), and the relationship between SPD earths and the earthing of the associated instrumentation or other equipment with which the devices are used are also considered.
Surge Protection for Intrinsically Safe Systems - This publication discusses the nature of the threat to intrinsically safe instrumentation in hazardous areas from voltage surges induced by lightning or other causes. The practical application of surge protection devices (SPDs) taking into account the approvals requiredis also considered.
Surge Protection for Zone 0 Locations - This note discusses the surge protection requirements of intrinsically safe circuits entering a Zone 0 hazardous area. It analyses the potential gradients generated by lightning strikes and their possible routes of invasion. The alleviation of the problem at the zone 0 interface transfers the problem elsewhere and an adequately safe pragmatic solution is proposed.
Surge Protection for Weighing Systems - An Application Guide - This publication discusses the nature of modern weighing systems and describes the various methods by which surge protection can be applied to load cells (digital and conventional), to control systems, etc., within the weigh cabin and to external system links.
Surge Protection for Local Area Networks - This publication discusses ways in which Local Area Networks can be damaged by lightning-induced transients, and how they can be protected economically.
Surge protection for electrical power installations - This publication discusses the affects of surges and lightning induced overvoltages on ac power systems. The note will introduce the source of many common transients and surges and suggest the application of surge protection devices in this area. Finally, typical examples are shown for common installations.
Lightning & surge protection for fieldbus systems - This publication contains a brief introduction to fieldbus systems. It continues by describing the surge protection necessary to protect such systems from the detrimental effects of lightning and other surges.
System Reliability and Surges - This article from Intech and Chris Towle of MTL discusses the risk that lightning-induced surges pose on a process plant.
Reliability, Availability, Maintenance, Return on Assets and Surge Protection - In this article Anthony O Bird discusses the appropriate level of surge protection that when applied to a process plant, reduces equipment fialure directly, increases plant availability and indirectly frees the maintenance team up to perform a more proactive role.
Surge Protection for Offshore Platforms - This paper discusses the vulnerability of various electrical and electronic systems against the impact of a lightning storm on an offshore platform.
Washington Gas - True Story - This paper points out the benefits to Washington Gas from their invested in surge protection to safeguard their equipment and reduce associated maintenance expenses.
Reliability of Surge Protection devices used with fieldbus systems - MTL instruments.
Surge Protection for Fieldbus without Performance Limitations
This article discusses a complete surge protection solution for an entire Foundation Fieldbus system without performance limitations.
Lightning and surge protection in emissions monitoring - Donald Long - At any given moment, there are over 1,800 thunderstorms occurring - The 1,000-ft stacks at electrical power generating plants are huge lightning rods reaching up into the sky. The very same stacks, selective catalytic reaction (SCR) beds, ammonia injectors, and precipitators, only now carrying expensive nitrogen oxide/sulfur dioxide (NOx/SO2) emissions monitoring equipment and associated power and instrumentation cabling, take on nature's fury in the form of potentially 200,000-ampere bolts of lightning. How can one effectively deal with this phenomenon? How does lightning get into the continuous emissions monitoring system (CEMS)? Is this the only form of surge? Is proper grounding the answer? Thanks to ISA and InTech.
Specification - Electrical and Instrumentation Enclosures
Typical Instrument and Electrical Enclosure Specification Index
The Following typical Index will assist in the preparation of a specification for an Instrument / Electrical Enclosure.
Introduction
Scope
Regulatory Considerations
Definitions
Abbreviations
Holds
Cross References
General Requirements
General
Location Of Equipment
Certification
Service and Environmental Conditions
Control Panel Construction
Indoor Control Panels
Outdoor Instrument Control Panels
Vendor’s Standard Control Panel
Tropic Proofing
Cabling Support
Cable Termination
Cable Transits
Cable Glanding
Control And Protection Equipment
Control Fuses
Control Switches And Pushbuttons
Indicating Lights
Electrical Instruments
Terminals
Power Distribution
Wiring
Installation Of Wiring
Earthing
Pneumatic System
Lighting
Ventilation and Cooling
Anti-Condensation Heaters
Fire Detection and Protection
Nameplates And Labels
Surface Preparation, Protective Coating And Painting
Lifting
Fire Rating
Inspection And Testing
References
Appendices
Appendix 1 Control Panel Data Sheet
Appendix 2.0 Nameplates
Uninterruptible Power Systems
The following Technical Information is from Falcon Electric Inc.
10.11 The True Cost of UPS and Batteries - A Tutorial - This is a brief discussion of the present day state of uninterruptible power supplies (UPS) under 10kVA, the largest UPS market segment, and their battery technology. They make up the bulk of the UPS units installed worldwide for business, industrial, scientific, IT and home applications. Since the UPS market is very large the UPS business has become very competitive, with a large number of domestic and international UPS manufacturers to choose from. Unfortunately, the selection is so large that consumers off all types, from a scientific laboratory to automated production, are often mislead into buying a UPS on price alone, without fully understanding what they are buying or available options. For home users this is typically not a problem, as they simply want to backup their home computer long enough to allow the operating system to perform an orderly shutdown. For the other applications referenced, users face a costly learning experience if they buy a UPS on cost alone.
Standby Power Supply (SBS) and Uninterruptible Power Supply (UPS) Tutorial - The following will guide you through successfully determining the type and level of power protection equipment required for your specific environment - from falconups.com.
Harsh industrial power environments demand high-level power protection: The right UPS can meet that demand - Michael Stout and Michael Gibson - When the discussion of uninterruptible power systems (UPS) arises, most people think of the little box they purchased to provide backup power to their home or office computers. They do not think of industrial-grade power protection. However, its incorporation into factory automation systems is a necessary security element - from the ISA and InTech.
UPS on the front line - Scott Siddens - Uninterruptible power supplies must be rugged, flexible to meet plant floor challenges - Computers in industrial plants and other types of technical operations have moved to the production floor. And with millions of dollars at stake in guaranteeing near-absolute power reliability for production lines, UPS manufacturers have been tasked with creating hardy systems that can withstand the extreme environments of manufacturing facilities. Several UPS products have come on the market in recent years to accommodate these requirements - from Plant Engineering.
Exploring UPS Systems - Michael Stout - Selecting a UPS that will meet specialized mission-critical requirements is a challenge even for the most experienced system engineer - from electronicproducts.com.
Power Conditioning: Selecting the best power conditioning type product for your specific power problems - Michael Stout - With the large number of power conditioning and protection products available on the market, the selection of a device that will provide the right level of protection needed for your specific power environment may seem a daunting task. The selection process can be simplified by first understanding the differing design methodologies available, in conjunction with understand ing how these methods relate to solving specific power problems.
Maintenance and Troubleshooting of Uninterruptible Power Supply (UPS) Systems & Batteries - This useful book is designed for you if you want to obtain a basic understanding of the application, installation, operation and troubleshooting of UPS systems and batteries.
Uninterruptible Power Supply - Planning and Installation Guide - This 24 page guide provides some excellent information - thanks to Solid State Controls.
Uninterruptible Power Supply (UPS) Frequently Asked Questions - from jetcafe.org.
Variable Speed Drives
AC and DC Variable Speed Drives - Application Considerations - Knowing what controller/motor package to use in a given situation is just one of the subjects covered in this overview of AC and DC drive application considerations - From Reliance Electric.
Top tips for specifying VFDs - Joe Kimbrell - Variable frequency drives can reduce energy consumption, improve real-time control and lengthen motor life. Selecting the right one for your application requires asking the correct questions - from Process OnLine and Automation Direct.
Silence of the Drives - Along with energy savings and other benefits, adjustable-speed drives have a downside—a tendency to generate disruptive electrical noise that must be minimized in the drive’s design and installation - Frank J. Bartos - They’re great for saving energy and optimizing automation systems, but adjustable-speed drives (ASDs) inherently produce high-frequency electrical noise. Fast switching transistors producing large voltage changes in the drive’s power section are the prime source of electrical noise, also known as electromagnetic interference (EMI). From Control Engineering.
Perplexing Variable Frequency Drive Vibration Problems - Brian Howes - Several unusual vibration problems have been seen recently that involve variable frequency drives and different types of driven equipment. The drives and motors are from different manufacturers and vary widely in size. The vibrations seem to be consistent in that there is a vibration frequency that remains constant as the shaft speed of the motor changes. Sometimes the vibrations are seen in accelerometer readings, but more consistently the vibrations are torsional. Generally, the solutions have involved changes to the software in the VFD control system - From Beta Machinery Analysis Ltd.
Variable Frequency Drives Optimize Performance and Protection of Offshore Oil Electric Submersible Pumps - Electric submersible pumps (ESP’s) offer the highest yield of most deep-well artificial lift systems, but suffer the highest frequency of expense and repair. This profile outlines how a careful selection of technologies, specifically the use of electric submersible pumps with variable frequency drives, can optimize the performance in well extraction on offshore oil production platforms - From Allen Bradley.
Variable Speed Drive Cuts Compressed-Air Costs and Helps Ensure Consistent Quality - Wayne Perry - Any evaluation about air-compressor selection will be based on a study of available technologies and existing equipment. In some instances, such as when there is continuous demand at full load, a fixed-speed, rotary-screw compressor may be the best solution. When the base load varies with an additional load, it might be best to consider supporting the base load with fixed-flow compressors and adding a unit with a variable speed drive (VSD) as a "trim" device to carry the variation in the load - From Impo.
The Digital Drive - Jonas Berge explains how variable speed drives can become an integral part of the digital plant architecture. The final control element that first comes to mind for process applications is the control valve, but variable speed drives (VSD) also variously referred to as a variable frequency drives (VFD), adjustable frequency drives, or frequency converters are also used as final elements in closed loop flow or pressure control. When it comes to set up, the sheer amount of configuration options available in a variable speed drive can seem overwhelming to technicians who have to commission them. A drive can have hundreds of parameters to customize AC motor controls for different applications. Most AC drives also have useful diagnostics about the motor and drive system and some even have predictive diagnostics. To help technicians more easily setup applications and diagnose problems, drive manufacturers now use electronic device description language (EDDL) to make drives easy to setup and diagnose by defining how the drives are displayed in the system. Bus technology and EDDL provide the ability to integrate instrumentation and controls with electrical and switchgear, enabling plants to freely select control system and electrical system independently, yet enjoy the ease of use as a result of tight integration - from Control Engineering Asia.
Clever pumping - All In One Drives Make the Water Industry’s Pumps Intelligent - Sanna-Kaisa Ehanto - The growing use of VSDs, particularly intelligent drives for pump control, represents a major departure from the standard operating practice of using control valves to vary fluid flow. With its low energy usage and low maintenance outlay, the total lifecycle cost of a VSD-controlled pumping system can be significantly less than traditional pump technology. Other VSD benefits include smoother start-ups and production changes, more precise control during continuous operation, and faster diagnosis of potential system problems before product quality or process operation is negatively affected. The emergence of intelligent pumps is a critical step forward in the evolution of process management. With embedded intelligence, VSDs can provide pump control, pump condition monitoring, protection and traditional energy saving benefits - from ABB Drives.
Building a Reliable VFD System - Brian Shuman - A Variable Frequency Drive (VFD) regulates the speed of a 3-phase AC electric motor by controlling the frequency and voltage of the power it delivers to the motor. VFDs offer many benefits; principle among them the ability to save a substantial amount of energy during motor operation. In that sense, these devices represent both an attractive, “green” engineering solution, and an economical choice. Other benefits worth mentioning include the following: they can maintain torque at levels to match the needs of the load, improve process control, reduce mechanical stress on 3-phase induction motors by providing a “soft start,” and improve an electrical system’s power factor. What’s more, legacy systems that now use throttling devices to regulate motor speed can be retrofitted with VFDs to make speed regulation much more efficient and precise. Special consideration must be given to the proper installation and operation of the overall system that comprises the VFD, the motor it controls, and the cable that connects them. This paper is primarily concerned with the motor-supply cable in the VFD/motor system. It looks at some fundamental cable design considerations, and presents suggestions for installation. However, to give the reader some context, it makes sense to first describe VFDs, their benefits and potential problems, and their relationship to the motors they control - from Belden.
Choosing the Right Cable for your Variable Frequency Drive (VFD) System - Brian Shuman - Like many engineering solutions, VFDs present not only benefits, but drawbacks as well. For example, the same fast switching rate of the transistors inside a pulse width modulated VFD that can accommodate an abrupt speed change in a motor (and offer precise control of processes) is also capable of generating unwanted noise in the drive system cable and in the drive itself. Electrical energy flowing in the cable contains frequencies as high as 30 megahertz. If this radio frequency energy is not contained within the cable, it can radiate out to interfere with the proper operation of nearby electronic equipment, less than robust, or commercial-grade Ethernet systems, and simple instrumentation wires even circuits that have absolutely nothing to do with the VFD system itself - from Belden.
Picking the Right VFD Cable - Reduce Problems and Increase Reliability -Variable-frequency drives (VFD) allow sophisticated control by AC motors by allowing their speed and torque to be precisely adjusted. Control is achieved by varying the frequency to the motor. It does not, however, send a pure sine-wave frequency to the motor. Rather it sends a series of pulses, whose width varies, to the motor. This technique—pulse-width modulation— supplies the drive with the same power profile as a sine-wave frequency. PWM also allows the effective voltage to the motor to be varied. While PWM provides an excellent way to control a motor’s speed and torque, it creates several phenomena that can affect the power, create noise, reduce the life of the cable, and disrupt operation of the drive system. Understanding these phenomena explains why selecting the proper VFD cable is important to maintaining reliable, long-term operation - from Alpha Wire.
Cable Alternatives for PWM AC Drive Applications - This paper describes an alternative solution for cables used with Insulated Gate Bipolar Transistor (IGBT) Variable Frequency Drives (VFDs). New IGBT technology has introduced voltage stresses on motors and cables that leads to unpredictable system performance and reliability. This paper includes a performance and cost comparison between a continuously welded armored option, the option of lead wire in conduit, and a proposed shielded tray cable. Unique physical characteristics of the cables are discussed. A proposed cable with increased insulation thickness is discussed that insures long-term cable service life under VFD operation, while the shielded coaxial braid contains VFD EMI emissions. Other applications, options, and termination considerations with respect to the petro-chem industry is discussed. Cable performance is documented with theoretical and experimental support. From Belden.
The Following Technical Papers are from Rockwell Automation.
The Drive for Harmonic Balance - Peter Tomazic - The presence of harmonics can drastically alter the quality of the power provided to electrical systems and may affect equipment on that supply. this paper explains how harmonics are generated, why they are a problem and discusses various engineered solutions that can mitigate their effects - Thanks to www.processonline.com.au.
EMI Emissions of Modern PWM AC Drives - Gary L. Skibinski, Russel J. Kerkman, and Dave Schlegel - This article provides a common understanding of the EMI issues and provides simple pre-installation and post installation guidelines useful for all interested parties involved in industry application of adjustable speed PWM ac drives. From Rockwell Automation.
Interaction of Drive Modulation & Cable Parameters on AC Motor Transients - R. Kerkman - This paper investigates over-voltage transients on ac induction motors when connected through a cable of arbitrary length to a Variable Frequency Drive (VFD) consisting of a Pulse Width Modulation (PWM) inverter with Insulated Gate Bipolar Transistor (IGBT) power devices. From Rockwell Automation.
Straight Talk About PWM AC Drive Harmonic Problems and Solutions - Though much has been written about harmonics and related issues with respect to AC drives, many drives users still seek clear answers to some basic questions. The purpose of this paper is to provide the interested reader with some basic information regarding AC drives and harmonics with a simplified explanation of harmonics and power factor, showing how both can affect a distribution system. It is the intention of the author to dispel some of the myths as well as point out legitimate concerns, show some viable solutions and their pros and cons.
Considerations for the Use of AC Induction Motors on Variable Frequency Controllers in High Performance Applications - Until recently the majority of AC variable speed drives have been applied to variable torque, pump and fan applications. Advances in drive technology have led to the use of induction motors in high performance applications that exceed the capability of motors designed for operation on sine wave power. These applications, which have traditionally been served by DC systems, have created the need for definite purpose AC induction motors designed specifically for operation on adjustable frequency controllers. This paper will discuss many of the considerations for a successful application and will highlight the limitations of standard motor designs.
AC Drive Ride - Through Techniques - While most AC drive applications do not require the drive to ride through a power interruption, many of those that do are crucial to a process. In those applications where ride through is required, it is often very important that the ride through provided meets the demand of the application to the extent that the process is not adversely affected. The shear number of variables between applications, and variations in drive features of different drives and drive manufacturers can make handling ride through a real challenge.
Line Reactors and AC Drives - Quite often, line and load reactors are installed on AC drives without a solid understanding of why or what the positive and negative consequences are for adding this piece of hardware. The purpose of this document is to provoke some thought on the part of the person(s) responsible for the successful installation of the drive, and to provide some guidelines as to if, where and when a reactor is needed and what size reactor to use.
Harmonic Calculators - Tool for determining how much voltage and current distortion might exist on your distribution system when operating non linear loads. This program is not intended to determine harmonic distortion with single phase loads. The analysis with single phase load is quite different from analyzing a 3 phase ac motor circuit. For single phase circuits, a distorted current wave form can place more stress on the supply system. For a 3 phase motor circuit converted to variable speed, the distorted current wave form does not place more stress on the supply system if the reactive component of current is removed.
Eliminating Voltage Notching on the Distribution System - When Silicon Controlled Rectifiers (SCRs) are used in electrical controls, it is possible to experience line voltage distortion in the form of "notches" in the waveform. The types of equipment that utilize SCRs in converters or rectifiers, to change the ac line voltage to a dc voltage, and thus experience notching include DC motor speed controls and induction heating equipment.
Installation Considerations - In the last few years, Adjustable Speed AC Drive (ASD) manufacturers have migrated from Bipolar Junction Transistor (BJT) semiconductors to Insulated Gate Bipolar Transistors (IGBTs) as the preferred output switching device. The advantage of IGBTs over BJTs is that device rise and fall time switching capability is 5 - 10 times faster, resulting in lower device switching loss and a more efficient drive. However, for a similar motor cable length as the BJT drive, the faster output voltage risetime of the IGBT drive may increase the dielectric voltage stress on the motor and cable due to a phenomenon called reflected wave. Faster output dv/dt transitions of IGBT drives also increases the possibility for phenomenon such as increased Common Mode (CM) electrical noise, Electromagnetic Interference (EMI) problems and increased capacitive cable charging current problems. This paper is discusses these issues and give solutions for each phenomenon.
Drive and Motor Basics - An adjustable speed drive is a device that controls speed, and direction of an AC or DC motor. Some high performance drives are able to run in torque regulation mode.
Pulse Width Modulated (PWM) - A short technical description.
Adjustable Speed Drives and Short Circuit Currents - Do all Adjustable Speed Drives contributed current to a line short circuit? Per IEEE standard 141-1993 (Redbook), section 4.2.5, "adjustable speed drives can contribute current from the motors to a short circuit..." This statement has led to confusion regarding adjustable speed drives and short circuit currents. The statement is true for some adjustable speed drives such as dc drives and CurrenSource Inverter (CSI) drives, but incorrect for PWM adjustable frequency drives.
Wind Farm Turbines
Offshore Wind Farm Electrical Connection options - a paper by W.Grainger and N.Jenkins- Thanks to the offshore wind energy network.
Instrumentation and Initial Evaluation of the 2.5MW Bockstigen Off Shore Wind Farm - Thanks to the offshore wind energy network.
Other Offshore Wind Energy Network Articles
Integration of Large Wind Farms into UtilityGrids - (Part 1 - Modeling of DFIG) - ABB Inc.
Integration of Large Wind Farms into Utility Grids - (Part 2 - Performance Issues) - ABB Inc.
Development and Analysis of a Novel Vertical Axis Wind Turbine - Paul Cooper and Oliver Kennedy - This paper describes the development of a novel vertical axis wind turbine used for teaching and research purposes. The device is designed to operate at low tip speed ratios and features blades that are symmetric about the mid-chord plane. The blades are actively pitched by means of a mechanical system so that the chord of each blade rotates by 180º for every revolution of the main rotor. One of the attractions of the device is that it is self-starting and produces relatively high torque. A multiple streamtube analysis of the device has been developed and numerical predictions for the performance of the device are presented. Commissioning and field tests of a prototype are described and some preliminary performance results are presented and discussed - From the University of Wollongong.
Effects of Complex Wind Regimes on Turbine Performance - Elisabeth Rareshide, Andrew Tindal1, Clint Johnson, AnneMarie Graves, Erin Simpson, James Bleeg, Tracey Harris and Danny Schoborg - Wind turbine power performance for the annual energy production calculations of wind farms has traditionally been modeled assuming a set of simple and average input meteorological conditions. Turbine power curve tests are also performed with this assumption, based on criteria defined in the IEC 61400-12-1 [1] standard. While this approach has proven to be adequate for the wind power industry for several years, the increasing size of wind turbines—coupled with an improved awareness of the wind flow variation throughout the boundary layer—has generated concern that the effects of complex meteorological conditions on turbine power performance are not well understood - from Garrad Hassan.
NEL have a Number of Useful papers on Wind Turbines - These include Wind turbine power performance measurements, Types of small and micro wind turbines and Conversion of wind energy into electrical energy - you will need to register to get these.
Electrical and Instrument Wiring Terminals
Jump to Subject:- Electrical and Instrument Wiring Terminals Technical Data | Termination and Electrical Connection Tools | Other Electrical and Instrument Terminal Links
Electrical and Instrument Wiring Terminals Technical Data
It is important that terminating and making off terminals is undertaken by fully competent electrical tradesmen. Quality crimping tools, terminals and accessories should be used.
Cable Termination Practices Simplified - Proper cable termination practices are vital for the complete and accurate transfer of both analog and digital information signals. This useful article from EC&M covers this.
Cable Termination Techniques - There are a variety of termination methods for cable. The termination method utilized depends basically on the system installed, type of cable used and type of connector. Using the proper termination method allows for good mechanical and electrical integrity. No matter what type of termination you will be performing, the most important thing is to use the proper tools and materials for the type of termination. For example, a crimp using pliers will work, but using a crimp tool and the proper die designed for your type of cable and connector is better. Using the proper solder type and the right temperature for solder type connections will ensure a lasting connection. We will review four basic termination techniques. This is just to provide some general guidelines. The termination method may vary somewhat based on system requirements and connector manufacture design methods. From West Penn Wire.
Connector Termination/Basic Guidelines - There are a variety of termination methods for cables. The termination method utilized depends basically on the system installed, type of cable used, and type of connector. Using the proper termination method allows for good mechanical and electrical integrity. No matter what type of termination you will be performing, the most important thing to remember is to use the proper tools and materials for your type of termination. For example, a crimp using pliers will work, but using a crimp tool and the proper die designed for your type of cable and connector is better. Using the proper solder type and the right temperature for solder type connections will ensure a lasting connection. This paper will review some basic termination techniques and provides some general guidelines. The termination method may vary somewhat based on system requirements and connector manufacturer design methods. From West Penn Wire.
Basic Electrical Training Course - This excellent 14 page pdf from Deutsch Advanced Interconnect is focused on the technology around connectors. This article is not an attempt at a basic course in electronics - rather, it is a course that will help you understand the electrical requirements that pertain to connectors. It’s pretty basic stuff - we promise not to get much heavier than Ohm’s Law and a few buzzwords. You’ll also be introduced to wire and cable so you’ll have a better understanding about connector applications.
Corrosion Resistance of Electric Wire Terminals Used in Harsh Industrial Environments - Industry reports indicate that 50 to 60 percent of electrical downtime has been traced to open or intermittent connections.1 Harsh industrial environments increase the risk of corrosion and chemical attack on metals used in wire terminal connections, potentially affecting electrical reliability. Engineers designing industrial control products must apply sound judgment in material selection and wire clamp design along with rigorous test methods to ensure reliable long term performance under harsh field conditions. Accelerated corrosion testing is an important tool for use in product designs such as wire terminal systems. Test methods such as salt spray testing have traditionally been used to evaluate corrosion resistance but can seldom be correlated to actual field performance. Other methods using corrosive gas mixtures have been developed to better correlate with field conditions. This paper studies corrosion resistance of wire terminal connections made from a variety of materials and protective platings and coatings. Accelerated test methods using both salt spray and corrosive gas mixtures were applied. The results show that each base metal and protective coating has it's strengths and weaknesses. Steel with zinc-trivalent chromate protective coatings performed well but vary significantly depending on the thickness of zinc, type of chromate, and use of sealers. Nickel-plated brass performed well except in environments with high concentrations of ammonia. Stainless steel provided the best and most universal corrosion resistance. The information presented in this paper can be applied to make more knowledgeable product selection decisions that will help ensure long term reliability of electrical connections used in industrial control applications - From Rockwell.
A Systems Approach to Functional Terminal Block Design - Consider where signals are processed in measurement, conversion and regulation systems - Carsten Luckheide - Ideally, functional terminal blocks should be easy to use, provide secure connections and make it simple to bridge terminals, whether or not they are adjacent. By taking a systems approach to functional terminal block design, though, a single block can be adapted to different connection requirements - from plantservices.com.
Wire & Cable Termination Options - How to complete your electrical assembly - Whether it’s a Wire Harness or a Cable Assembly, find the best way to terminate the ends. This is a quick reference chart of common termination options to help decide which is best - from DSM&T.
Connection Tips - From the Friendship Sloop Society (Not industrial tips but pretty relevant anyway).
U Tube Videos
Proper Wiring Termination - Tips, Tools and Methods
The following Technical Data is from Weidmüller Pty Ltd:
- Connection Technologies for the World of Automation - In today’s tough markets, cost-cutting has long since ceased to be a sufficient means of remaining competitive. Developing ever more compact components has become a crucial factor for concepts to succeed. Weidmüller can help you to master this tricky task while developing and producing automation systems by supplying optimum solutions.
- Modular Terminals Technology - Please be patient with this download from Weidmüller (3.4 Meg), it gives full catalogue data on their terminal range and technical information on what terminals to use.
- Precisely Connecting Signals in Process Control Systems - Proper signal transmission is often an immense project, particularly in process plants: Several thousands of field signals need to be wired to the DCS (Distribution Control System). In doing so, the clear and simple connection of the wires, their shielding, the protection against lightning and surges, as well as the conversion of the signals must be implemented in a precise and efficient way. In response to these requirements, Weidmüller has designed a variety of precisely tailored solutions for connecting signals in process control systems.
- WMF the New Way of Marshalling - This video details a new way of Marshalling a Distributed Control System – It has considerable advantages over the traditional methods.
- Spring Connection - Wherever time is short, Weidmüller's Tension Clamp System is the best choice. It is rapidly wired up, easy to use and offers 100% vibration resistance.
- Solder Connection - Soldering guarantees a good electrical connection. Weidmüller offers a choice of Terminals to match this Connection Technology.
- Spring-Clip Connection - Weidmüller's patented Termipoint Connection System for use with pneumatic gun.
- Pressure Clamp Connection - Weidmüller's patented pressure Clamp Connection for large conductors is easy to use and low maintenance.
- Top Connection - One access direction for conductor and tool with Weidmüller's tried and tested Screw Type Connection. This connection method guarantees a high contact force and a gas-tight connection.
- Push In Terminals - Save Time with Fast Push In Technology New Extended Range of P-Series Terminals. The cornerstones of this concept is the "Push In" connection technology which enable a reduction in the terminal variants whilst providing incredible cost savings.
- Quick Selection Guide Modular Terminal Blocks - Need a terminal? Choose from the huge range detailed here.
U Tube Videos - There are a useful series of videos on U Tube giving examples of how to connect using Weidmüller terminal blocks and accessories.
Screw Type Terminal Blocks W-Series
Tension Type Terminal Blocks Z-Series
IDC Type Terminal Blocks I-Series
Push-In Type Terminal Blocks P-Series
Weidmüller FieldPower Solution - Animation of Weidmüller FieldPower Solution for Power Distribution along conveyor belts.
Weidmuller Connection Technology W series Clamping Yoke - This video details the mechanics of the clamping yoke – it is pretty “cool”.
Weidmuller Connection Technology Z series Tension Clamp - This video details the mechanics of the Tension Clamp.
Weidmuller Connection Technology P series Push In - This video details the mechanics of the Push in Technology.
Technical Appendix - Includes Connection systems, Definitions of the various types, Materials – Insulating materials, Materials – Metals, Standards, directives, terminology, General technical information, Electrical data, Installation instructions, ATEX Modular terminals for explosive conditions, ATEX directives, codes and cross-connection instructions.
The following links are from Entrelec;
- Screw Clamp - Technology remains the most popular in connection devices. The screw clamp is the most recognized and widely used connection technology.
- Spring - Technology is a fast growing standard in screw-less connection. Spring connection technology continues to grow in popularity in the industrial and commercial markets, including automotive and railway industries.
- IDC (Insulation Displacement Connection) - Technology - is the newest, fastest, and most innovative of screw-less connections. An insulation displacement connection (IDC) terminal block, and a tool that cuts, strips, and inserts the wire into the connector.
Termination and Electrical Connection Tools
The following Technical Data is from Weidmüller Pty Ltd:
- Cable Connection Tools and Accessories - Details on a range of these useful tools.
- Just the Right Tool for your Application - This informative brochure is sorted by application areas. That way you can quickly find the quality tool you are looking for. It also contains useful tool tips.
- Cutting Tools - A large number of cables and conductors in many different types and designs are used to connect electrical and electronic components. The cables and wires must be accurately prepared for the various types of connection. The quality of the cutting process is therefore of critical importance. Mechanical efficiency together with the special cutting pattern reduces the manual force required to a minimum.
- Stripping Tools - After a conductor has been cut it is then prepared for the next step or for crimping. For this purpose, a specific length of the conductor insulation has to be removed, while preventing damage to the conductor. The length of the conductor insulation to be removed depends on the terminal clamping point or the crimp to be processed. Professional stripping tools guarantee perfect results due to precise adjustment of the tool to the corresponding insulation and the conductor cross-section. Precision tools by Weidmüller guarantee that the user will always obtain consistent, reliable stripping results. “Stripping” means the cutting and removal of the insulation. The methods required to perform this task correctly are detailed in this download.
- Crimping Tools - After stripping, appropriate contacts or wire end ferrules can be crimped to the cable end. Crimping produces a reliable connection between conductor and contact, and has more or less completely replaced soldering. Crimping describes the production of a uniform, nondetachable connection between conductor and connecting element. This should be achieved exclusively by the use of a high-quality precision tool. The result is a safe, reliable connection in both electrical and mechanical terms.
- A Range of Other Useful Termination Tools and Accessories - Includes wire end ferrules, pliers, connectors of various types, ESD pliers, testers, automatic machines and much more.
U Tube Videos
Weidmuller CTI 6 Crimping Tool - This 'U Tube' video shows how to use the tool effectively.
Weidmuller PZ 3 Wire Crimping Tool - This video shows the correct use of this crimping tool for wire-end ferrules with or without plastic collars (AWG 24...16). The PZ 3 produces a square crimp.
Weidmuller PZ 6 Roto Wire Crimping Tool - This Video demonstrates the correct use of this professional crimping tool for wire-end ferrules with or without plastic collars (AWG 24...16). The PZ 6 Roto produces a trapezoidal crimp.
Weidmuller PZ 16 and PZ 50 Wire Crimping Tools - Video demonstrating the use of these professional tools for crimping wire-end ferrules with or without plastic collars. The PZ 16 and PZ 50 produce indent crimping.
Weidmuller CTN 25 D4 and HTN 21 AN Crimping Tools - Video demonstrating the use of these professional tools for crimping uninsulated cable lugs and connectors.
Weidmuller CTX CM 1.6 Crimping Tool - Video showing use of this professional tool for crimping turned contacts.
Weidmuller HTF RSV 16 Crimping Tool - This video demonstrates this professional tool for crimping RSV and DSTV-HD contacts.
Speciality Control Systems - Weidmuller Marking Tags - This video details a wide variety of marking options for your terminal block and rail assemblies. Unfortunately, understanding all of these options can be quite a challenge! It also highlights the most common terminal block marking solutions.
Technical Dictionary - This excellent 44 page document includes Certificates, Electrical data including clearance and creepage distances, and Current load curve. It also covers;
General Technical Data - including information about CE marking, EMV directives, Protection types, Converting AWG conductors to mm2, Gauge pin,
Materials - including Insulation materials, Metals, Current loading curves,
Connection types
ATEX
Terminals - including Regulations / definitions, Assembling terminal strips, Connecting terminals, Use of aluminium conductors, Definition of the various types, Ex terminals.
Relay couplers/Opto-couplers
Overvoltage Protection
Tools - Cutting, Stripping, Crimping.
Hazardous Areas Technical Guide - This excellent 90 page technical guide from Weidmüller is a large pdf download at 7 Megs, however it is worth the wait!
Applications in the Oil and Gas Industry - This application bulletin illustrates the practical concepts and special features in both the upstream and downstream sectors of the oil and gas industries.
Other Electrical and Instrument Terminal Links
XB IEC Terminal Blocks - versatility, quality, and reliability - This brochure details the different designs utilised by the Eaton range of terminals.
Video - XB Terminal Blocks - Details the features of this range of terminal blocks - from Eaton.