NEC: Identification Requirements for Branch Circuits, Part 1

The requirements for identifying branch circuit conductors aren’t all in one place, and they aren’t straightforward. But they begin in Sec. 210.5 of the 2014 NEC.

Your first step in the identification process is to decide which of these three types the conductor is:

• Grounded conductor.
• Equipment grounding conductor
• Ungrounded conductor.

For the first two in the list above, 210.5 refers you to elsewhere in the NEC.

For ungrounded conductors, the 2014 Edition of the NEC provides a much longer text of requirements than the 2011 NEC, including nearly half a page of new material. The 2011 NEC requirements were all-new, and nearly all of the 2014 version text replaces what the 2011 NEC provided. Even the 2008 version of these requirements was heavily updated from  the 2005 NEC text.

Yes, it has gotten complicated. Let’s try to sort this out, starting with the requirements for identifying the grounded conductor.

First, what is the grounded conductor? It’s usually, but not necessarily, the neutral. It’s a system or circuit conductor that’s intentionally grounded [100]. This differs from a grounding conductor, which is a conductor that extends the ground connection [100]. The identification requirements are in Sec. 200.6, Means and Identification of Grounded Conductors. The requirements vary, depending upon which of five categories the conductor falls under.