Preparing, Responding & Recovering from a Natural Disaster

Key Steps to Help Electricians Assess Whether Damaged Industrial Electrical Systems Should be Repaired or Replaced Natural disasters can strike in an instant and leave...

Water-Damaged Electrical Equipment

Water and electricity do not mix. Follow this guide to quickly see what equipment must be replaced and which electronics may be reconditioned. Any...

Common Misconceptions Related to the Design, Installation, and Use of Electrical...

During many years of writing various articles in this publication, I am fortunate to receive numerous emails with questions and comments from the readers....

PV Systems Math — Sample Calculations

Looking at the PV array in a PV system, many installers and inspectors are confused by new system voltage calculations that may be required...

UL Question Corner — PV rapid shutdown inside the array, and...

Question Effective January 1, 2019, the requirements for PV rapid shutdown inside the array boundary went into effect in the 2017 NEC Section 690.12(B)(2). Are...

UL Question Corner — Introducing the UL Product IQ Database

Question I tried accessing UL’s Online Certifications Directory and was redirected to UL Product iQ database requiring registration. Has UL’s Online Certifications Directory been replaced...

Questions From the Field

Question I am hoping you may be able to help me with the interpretations or point me to the correct resource. I am having trouble...

Voltage Drop Calculations

Voltage drop is only mentioned in some sections of the NEC as informational notes, and is required to be calculated in other sections of...