Can someone confirm this apartment/townhouse load calculation nuance for me?

4316 Views 1 Reply 2 Participants Last post by  99cents
I took a code course last fall, and it's a small rule difference that I noticed after doing many different building calculations. It's a bit complicated, so I couldn't sum it up for the title, but i'm wondering if someone can just confirm that i'm doing it properly.
(Yes I got all the questions marked correctly in class, but i'm just looking for some outside verification. Just making sure I'm not crazy!)

When calculating for a house, apartment, or townhouse, you will always have a minimum amount. Like 60A for an apartment.
But if you calculate, say, 11.5kw for an apartment, you use 12.48kW (60A*208v) for the individual apartment feeder (rule 8-202 (1)(b)), BUT you use the 11.5kW calculated at their respective percentages for however many units there are for the building service.

When doing this for a townhouse, however, say you have a quadraplex with 90m^2 townhouse with a 95A calculated load. You would use 100A for the individual feeders, and 100A (not 95A) for each unit when calculating the whole service.

So in the apartment example you use the smaller of the 2 loads for the building service calculation, and in the townhouse you don't. Have I got this right?
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99cents

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Estwing magic
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Yes, for multifamily you use actual suite watts and house load (with the percentages) to determine main feeder size.

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