Note: This article is based on the 2002 NEC. Even if you work with stamped drawings, you'll eventually need to do commercial load calculations in the field or on a licensing exam. The National ...

In Part 1, we looked at specific types of commercial loads. Let’s use some examples to show yet another difference in demand factors. If you were to watch daily operations at a marina [555.12], you’d ...

The electrical panel, also known as the service panel, is the control center for all the electrical circuitry in a residence. Today’s panels are bigger than earlier versions. They have to be, because ...

Members of the National Fire Protection Association (NFPA) recently concluded discussions on updating Article 220.12 of the NEC (National Electrical Code) to align with a series of energy codes, as ...

What do turf wars, battle lines, and tug of war have in common? They are all being mentioned by people involved in the creation of two rival commercial HVAC load calculation standards, one from the ...