dougbert
Solar Addict
I don't mean to hijack this thread, but this type of discussion needs to be in 1 place I think.I have a single 6000XP and PowerPro ESS that I will be using strictly for emergency power backup for now.I suspect that I will probably add a second battery next year along with some PV. Going back to the OP's original question...What size breakers for the "grid input" and "AC output" when using #6 copper.I have a leftover piece of 6/3 NM-B I want to use.I have attached a drawing of my layout. I don't think I will need a 2nd 6000XP in the future.Thanks for your input.
NM-B (romex) has a current limit of 55 amps (60 degree C), thus a 50 amp breaker. THHN wire has a nominal 90 degrees C rating and can handle 75 amps, BUT panels are set for 75 degree C, can handle 65 amps, thus a 60 amp breaker
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Cerrowire Resources - Ampacity Charts
Ampacity is the maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. Cerrowire's ampacity chart helps calculate the load requirement for a circuit.
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