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donf
Sizing the OCPD

I need to do a service drop (single phase - 3 wire type XHHW - copper)cable.

Because of a daily summer time temp of 113 (F) I need to factor the correction 0.82 into the calculation.

Based on the math I did, I would need a 1350 kcmil copper cable (300 Amps) to feed 246 amps after the correction. 300 X 0.82 = 246 amps. Question, do I have to use a 300 Amp breaker or a 250 Amp breaker?

Thanks in advance

sparky1
Re: Sizing the OCPD

250 would be fine. you have to do all the correction factors to protect the wire, not the breaker

NEC
Re: Sizing the OCPD

113 F Temp? I am just laughing. Where do you live? Hell?

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