• We will be performing upgrades on the forums and server over the weekend. The forums may be unavailable multiple times for up to an hour each. Thank you for your patience and understanding as we work to make the forums even better.

PI: 210.19(A) Number One

Status
Not open for further replies.

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Next a couple PIs for 210.19(A).

The first is for clarity and proper use of the defined terms. This is a topic that Don and I (and maybe others) submitted PIs for during the 2023 cycle, hopefully the CMP will find this approach of adding headings to be more agreeable.

Cheers, Wayne

(A) General.
Branch-circuit conductors shall have an ampacity not less than the larger of the following and comply with 110.14(C) for equipment terminations:
(1) Without Adjustment and Correction Factors. Where a branch circuit supplies continuous loads or any combination of continuous and noncontinuous loads, the minimum branch-circuit conductor size shall have an ampacity not less than the noncontinuous load plus 125 percent of the continuous load in accordance with 310.14.​
Exception to (1): If the assembly, including the overcurrent devices protecting the branch circuits, is listed for operation at 100 percent of its rating, the ampacity of the branch-circuit conductors shall be permitted to be not less than the sum of the continuous load plus the noncontinuous load in accordance with 110.14(C).
(2) With Adjustment and Correction Factors. The minimum branch-circuit conductor size shall have an ampacity not less than the maximum load to be served after the application of any adjustment or correction factors in accordance with 310.15.​
Exception to (1) and (2): Where a portion of a branch circuit is connected at both its supply and load ends to separately installed pressure connections as covered in 110.14(C)(2), an allowable ampacity in accordance with 310.15 not less than the sum of the continuous load plus the noncontinuous load shall be permitted. No portion of a branch circuit installed under this exception shall extend into an enclosure containing either the branch-circuit supply or the branch-circuit load terminations.

Statement of Problem and Substantiation for Public Input

The proposed section headings are borrowed from 690.8(B) and clarify the two different uses of the word "ampacity" in this section. As currently written, the use of the word "ampacity" in section 1 is confusing, because the definition of ampacity and section 310.15 lead to an interpretation that the term "ampacity" always includes the application of adjustment and correction factors.
 

wwhitney

Senior Member
Location
Berkeley, CA
Occupation
Retired
Oh, and I made basically identical PIs for 215.2(A) and 230.42(A) (just change the item headings), so rather than post those, I'll just note that here.

Cheers, Wayne
 
Status
Not open for further replies.
Top