Technical Articles

Technical Articles

IEEE 1584 – 125 kVA Transformer / Less than 240 Volts Exception

One sentence in the IEEE 1584 Standard, IEEE Guide for Performing Arc-Flash Hazard Calculations, frequently has people scratching their heads: Equipment below 240V need not be considered unless it involves at least one 125 kVA or larger low-impedance transformer in its immediate power supply. What does this sentence mean? What is so significant about 240 volts and 125 kilovolt-amperes? Download:  125 kVA / 240 Volt Exception       About Jim Phillips: Electrical Power and Arc Flash Training Programs –

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IEEE 1584 Two Second Rule

A lot can happen in two seconds. What may seem like the blink of an eye can feel like an eternity, especially during an arc flash. When calculating the incident energy as part of an arc flash study, sometimes the IEEE 1584 equations can produce unusually large values. Although many variables are included in these calculations, the two most significant are the magnitude of arcing short-circuit current and the duration of the arc flash. Question 1: How long? The duration

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Complete Guide to Arc Flash Hazard Calculation Studies

How to Perform an Arc Flash Calculation Study

This article by Jim Phillips provides an overview of how to perform an arc flash study. It was originally presented at the 2010 NETA Conference. InterNational Electrical Testing Association. BUY NOW Arc Flash Calculation Study Many separate codes, standards and…

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Predicting the Arc Flash Duration

Determining the arc flash duration is the most important piece of information in predicting its severity. The arc flash duration is usually dependent on how fast an upstream protective device will trip. The longer it takes, the greater the incident energy and resulting hazard. Download:  Arc Flash Duration   

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Get Ahead of It! – NESC Arc Flash Requirements

The NESC’s Arc Flash Requirements first appeared in the 2007 Edition. Determining how much incident energy could be available at a piece of equipment or location on a line is something you do not want to discover from a field test (accidental or intentional this means the only alternative is to predict it from calculations) Beginning with the 2007 NESC, The Arc Flash Requirements are:

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Simplifying Arc Flash Studies – Select the Arc Rating First

Begin at the End – What Answer Would You like to Have? Simplifying the arc flash study – Would you like to know a little secret about how to simplify an arc flash studies? Perform the study backward. Well, not actually backward, it just seems that way Performing the study: Arc rating > incident energy. An arc flash study is one method that can be used to determine the level of arc-rated clothing and personal protective equipment that is appropriate for protection

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DC Arc Flash Hazard Calculation Guide - Free Download

Arc Flash Boundary and Working Distance

Greater Distance = Greater Arc Flash Safety When a bomb goes off, the further you are from the explosion, the safer you will be. This same concept also applies if an arc flash incident occurs. Whether you are a properly…

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Arc Flash Warning Labels

Read the label? Use as directed? It sounds like I’m reading a prescription bottle. However, the warning label produced from an arc flash calculation study contains more than just the words Warning! Arc Flash and Shock Hazard It actually holds a lot of very specific information that can be used when preparing for work where electrical hazards may exist.

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U.K. Article – Arc Flash – Not Just an Electrocution Hazard – Part 3

Arc Flash – The need for risk assessment is embodied in European Law through directive 89/391 and is transposed into UK Law through Management of Health and Safety at Work Regulations. Most people are familiar with the general principles of prevention as laid down in these documents and in other UK regulations. They say that “Where an employer implements any preventative measures, he shall do so on the basis of the principles of prevention” shown below. The authors discuss how

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