ampere rating of disconnect for heating unit 115% or 125

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collier

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I have a heater with a minimum circuit ampacity of 209 amps. Is a 200 amp disconnect large enough?
I can find information regarding motors (115% of fla) and compressors (115% or branch circuit selection current-whichever is greater) but cannot find anything for resistant heater. The 200 amp disconnect would be large enough if the requirement were 115% of the full load amps of the motor plus the load of the heaters.

208 3 phase. motor 24.2 amps, heat strips 54kw

(actually this is a rooftop package unit with the heat strips much larger than the compressor load -the compressor and heatstrips can not operate at the same time)
 
Re: ampere rating of disconnect for heating unit 115% or 125

Section 424.2 tells us that "fixed electric space-heating equipment incorporating a hermetic refrigerant motor-compressor shall also comply with Article 440. This sounds like what you have, so I feel 440.12(A)(1) would apply requiring the disconnecting means to be rated at 115%.
 
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