by using the optional method to calc. residential load i determined 89 amps of load.9kw was elect heat which i multiplied by .4 to add to other loads. do you think i'm doing the right thing by using the existing 100 amp main breaker panel and 2-2-4 aluminum seu cable?there seems to be quite a diff in load results between standard method and optional method
optional residential load calc
- Thread starter tommyrice
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JoeStillman
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- West Chester, PA
You can only use 40% on the space heat if there are four or more separately controlled units. Otherwise it's 65%. Also, if the air conditioning load is more than 3.6 kW, (9 kW @ 40%) you have to use that instead of the heat load.
Remember, though, that all of the methods for calculating residential load give the maximum non-continuous load*. You don't have to multiply them by 125% to size the feeder and main breaker. So a properly calculated 89 amps is fine on a 100A service.
*(I called the NFPA once to confirm this.)
Remember, though, that all of the methods for calculating residential load give the maximum non-continuous load*. You don't have to multiply them by 125% to size the feeder and main breaker. So a properly calculated 89 amps is fine on a 100A service.
*(I called the NFPA once to confirm this.)
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