i have a sub 50 amp sub panel that i want to put in a detached maint/gar building. to save money on wire i am going to run two #6's for the lines and one #8 for the neutral(derating the neut)along with a #10 ground. my question is does this sound code compliant, we derate neutrals for the service feeders and this is going to be a feeder so it seems very complicit to me.
am i on the right page? any codes that i am missing which would forbid this derating? thanks guys, h20
By not knowing what your load is, I can't tell you that you can or can't derate the neutral. Also, I would be interested in how you terminate the neutral and ground wires in the sub panel. Where do you connect the Grounding Electrode Conductor in the sub panel?
#97409 - 02/18/0610:02 PMRe: sub panel detached building
Hold on. You must ALWAYS install a grounding electrode system for a detached building with more than a single multiwire branch circuit. It doesn't matter if your have three or four wires; with or without an equipment grounding conductor. see 250.32
#97412 - 02/18/0610:16 PMRe: sub panel detached building