Jim Phillips

Arc Flash Columnist

Jim Phillips, P.E., is founder of brainfiller.com and is an international trainer. He is Vice-Chair of IEEE 1584 Arc Flash Working Group, International Chair of IEC TC78 Live Working Standards and Technical Committee Member of NFPA 70E. He can be reached at jphillips@brainfiller.com.

Electric Current Through Tissue and Air: Protecting against shock and arc flash hazards

Jim Phillips

Basic electrical theory is that the greater the load is, the greater the current. Normally, the current flows through conductors and various electrical components, but what if the current takes a different path? What if it...

Figure 1: Absence of voltage tester | Panduit Corp.

Safety

May 13, 2022

Incident Energy and Arc Flash Boundary Calculations: How to perform an arc flash study, part 5

Jim Phillips

The final part of this series examines incident energy and arc flash boundary calculations for the 480V panelboard example used in this series. IEEE 1584—IEEE Guide for Performing Arc Flash Hazard Calculations defines...

Safety

Mar 15, 2022

Duration and Time Current Curves: How to perform an arc flash study, part 4

Jim Phillips

The duration of an arc flash is typically defined by how long it takes an upstream overcurrent device to operate and clear the fault. This requires using the device’s time current characteristic (TCC), which is based on the...

Safety

Jan 14, 2022

Time Considerations: How to perform an arc flash study, part 3

Jim Phillips

Time is everything when an arc flash occurs. The longer the duration, the greater the incident energy exposure, which is directly proportional to the duration. The 2018 edition of IEEE 1584 defines the arc duration, also...

Safety

Nov 15, 2021

Calculating an Arcing Fault Current: How to perform an arc flash study, part 2

Jim Phillips

An arc flash occurs when short-circuit current jumps across an air gap between energized conductors. The event is normally the result of initial (and inadvertent) contact between energized conductors that creates the short...

Table 1: Gap distance and arcing fault current

Safety

Sep 15, 2021

How to Perform an Arc Flash Study: IEEE 1584 takes it to a new level

Jim Phillips

Performing an arc flash study can be complex enough, but the latest edition of IEEE 1584—IEEE Guide for Performing Arc-Flash Hazard Calculations has taken it to a whole new level. A lot has changed since arc flash studies...

Safety

Jul 15, 2021

No Arc Flash Hazard Exists—Really? A dangerous assumption around calculated incident energy

Jim Phillips

I still hear this more than I should. Someone wants to list “no arc flash hazard exists” on the arc flash warning label. When I ask why, the response is usually along the lines of, “Because the incident energy is less than 1...

Safety

May 15, 2021

Remembering the Victims: The lessons of Electrical Safety Month

Jim Phillips

Once again it is Electrical Safety Month, and NFPA 70E continues to be at the forefront of electrical safety. However, not enough people are properly trained based on the requirements of this standard. Below are several...

Safety

Mar 15, 2021

Is It Off? Verifying absence of voltage with large incident energy

Jim Phillips

The 2021 Edition of NFPA 70E, Standard for Electrical Safety in the Workplace, introduces a new informational note to address the age-old dilemma: How do you verify absence of voltage when the calculated incident energy is...

Safety

Jan 15, 2021

More Than Just One Number: Understanding incident-energy calculations

Jim Phillips

Playing with fire When I was around 10 years old, I learned the “fine art” of playing with fire. I thought it was amazing to wave my finger directly through a candle flame without being burned. I also learned (the hard way)...

Table 1: Constant Duration-Vary Content; Table 2: Constant Current-Vary Duration; Table 3: Constant Incident Energy-Vary Duration and Current | Jim Phillips

Safety

Nov 13, 2020

How Much Is Too Much? Short circuit (fault) current

Jim Phillips

The 2020 Edition of the National Electrical Code and the 2021 Edition of NFPA 70E define the term available fault current as: “The largest amount of current capable of being delivered at a point on the system during a short...

An arrow shaped like a lightning bolt next to an illustration of an arc flash

Your Business

Sep 11, 2020

Training in a COVID-19 World: Meeting students’ needs with online education

Jim Phillips

Social distancing, self-quarantining, travel restrictions. It’s no secret, COVID-19 has upended business as usual. Is 2020 over yet? Before I go further, I truly hope this column finds you and your family safe and well during...

A teacher visible in a computer monitor, with a pile of books, leaves, a pencil, a file folder and a magnifying glass underneath