Grouch
Senior Member
- Location
- New York, NY
We always use the MOCP values that the AC unit manufacturer provides us with to indicate the breaker / fuse size feeding the unit.
However, just for my general knowledge... assuming the MOCP value is not provided, I can follow section 440.22(B)(1) to calculate it. This section states:
"the rating or setting of the branch-circuit short-circuit and ground-fault protective device shall not exceed the value specified in 440.22(A) for the largest motor-compressor plus the sum of the rated-load current or branch-circuit selection current, whichever is greater, of the other motor-compressor(s) and the ratings of the other loads supplied."
My question is where I bolded the text. Which 'value' are they talking about in 440.22(A)? Is the value equal to the rated load current *175% (or up to 225%)? Or is the value equal to the actual breaker / fuse size not exceeding the rated load current *175% (or up to 225%)?
However, just for my general knowledge... assuming the MOCP value is not provided, I can follow section 440.22(B)(1) to calculate it. This section states:
"the rating or setting of the branch-circuit short-circuit and ground-fault protective device shall not exceed the value specified in 440.22(A) for the largest motor-compressor plus the sum of the rated-load current or branch-circuit selection current, whichever is greater, of the other motor-compressor(s) and the ratings of the other loads supplied."
My question is where I bolded the text. Which 'value' are they talking about in 440.22(A)? Is the value equal to the rated load current *175% (or up to 225%)? Or is the value equal to the actual breaker / fuse size not exceeding the rated load current *175% (or up to 225%)?