Technical Articles

Electrical Power System Design and Analysis

Neutral Grounding Resistor

Impedance Grounding and Arc Flash

A short circuit happens when energized conductors accidentally make contact with each other and/or to ground. When that connection forms, the load and its impedance is bypassed resulting usually resulting in a very high magnitude of current. There are several fault types—three-phase, phase-to-phase, and line-to-ground, but the line-to-ground fault is by far the most common. You’ll often see numbers in the 70–80% of all faults falling into this category. Some say this number is even higher. Why so many line-to-ground

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Close-up of damaged electrical circuit breaker components

NFPA 70E 110.3 (J) Incident Investigations

NFPA 70E 110.3(J) Incident Investigations Electrical power systems, like all complex systems, are prone to failures. These failures can arise from a wide range of causes, including improper work procedures, faulty or inadequately maintained equipment, or human error, among others.

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Jim Phillips in his PPE

2021 NFPA 70E – Major Changes

Jim Phillips, P.E. Every three years I have the privilege of writing the NFPA 70E Changes article for National Electrical Contractor Association’s magazine: Electrical Contractor . The NFPA 70E 2021 edition of this standard will be available September 4, 2020…

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