NEC 430.24 - conductor sizing question

I mostly use IEC at work so I am not very familiar with NEC, so I have this question.

It seems to me that NEC 430.24 says that the conductor ampacity for at least 1 motor + anything else has to be 125% FLC of the largest motor + the sum of 100% FLC of each of the other motors, "plus the ampacity required for the other loads"

What do you do if you have a bunch of large non-motor loads and a few small motors? Do you still take the largest motor and sum the rest? And when they say "required," do they mean required per NEC (125% again of the largest non-motor continuous + 100% of the noncontinuous) or simply the sum of 100% FLC?

Thanks.

R2KBA said:

I mostly use IEC at work so I am not very familiar with NEC, so I have this question.
It seems to me that NEC 430.24 says that the conductor ampacity for at least 1 motor + anything else has to be 125% FLC of the largest motor + the sum of 100% FLC of each of the other motors, "plus the ampacity required for the other loads"

What do you do if you have a bunch of large non-motor loads and a few small motors? Do you still take the largest motor and sum the rest? And when they say "required," do they mean required per NEC (125% again of the largest non-motor continuous + 100% of the noncontinuous) or simply the sum of 100% FLC?

Thanks.

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You still have to comply with NEC despite having large non-motor loads and a few small motors. Often times NEC can be interpreted in different ways. Based on the scenario you proposed, I would say the conductors should be sized such that you take 125% of the largest motor FLA (albeit small) + 100% of each & every motor FLA on that same feed + 100% of all attachment loads.