Previously, we noted that the 2015 NEC added an Exception to the Table 220.12 minimum load requirements, to facilitate compliance with energy codes. But what if your application isn’t in that table?
It’s covered by either:
- 220.14 (Other Loads -- All Occupancies) or
- 220.16 (Loads for Additions to Existing Installations).
If you’re adding loads to an existing installation, apply 220.16; else, apply the other one.
Instead of a table with different occupancies, 220.14 contains a series of subsubsections (B through K) with different applications.
The two bookends are critical to understand. The NEC says if you are installing a load not listed in (B) through (L), calculate the outlet based on the ampere rating of the load served. This should probably refer to (B) through (K), because (L) is a requirement for anything not listed in (A) through (K). If you don’t find it there, use 180VA per outlet.
If it’s an existing installation and it’s:
- A dwelling unit to which you are adding loads for structural additions (or to a previously unwired portion) that exceeds 500 square feet, calculate loads per 220.12 and 220.14.
- Not a dwelling unit (or a previously wired dwelling unit to which you are adding new or extended circuits) calculate loads per 220.12 or 220.14 as applicable.
