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 ...

To avoid confusion, follow the NEC sequence when performing your circuit calculations. You'll see this sequence in each of the Annex D examples. You'll also see it in the structure of the Chapter 2 ...

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 ...

Not long ago a residential load calculation — also known as a heat loss calculation or a load calc — was something you had the luxury of skipping. There was a good reason for avoiding it. It was ...