For a branch circuit containing multiple 50A 250V outlets, 210.24 states that 6awg copper must be used for the "circuit wires". Does this mean that even though I'm using THHN in conduit and 75C is the lowest temp limiting device (my breaker), that I have to use 6awg instead of 8awg?
Actually I want to use 6awg for the hots to aid in voltage drop, but I would like to reduce the neutral to 8awg and the ground to 10awg. I do not want to use the conduit as a ground even it it was allowed, so don't ask.
If this were a single outlet or a fixed in place device I believe I could use wire as small as 8,8,8,10, and based on the device and unbalanced current, maybe 10awg for the neutral. Normally I wouldn't quibble about using larger conductors for neutrals and grounds, however based on my estimates, using a 8awg neutral and 10awg ground in my garage adds up to around $400 in copper savings alone.
Had an idea... Could I use 2-2-2-4 aluminum cable for the main run and splice down to 6-6-6-6 at each splice terminal block? Aluminum is sooooo much cheaper. Would that satisfy 210.24?
Brief background: I'm trying to add several 50A 250V outlets spaced around my 40X64' garage for welders or other mobile high power cord and plug equipment. Only one device is to be plugged in at a time so I want to wire all the outlets to one 50A breaker instead of 3-5 individual breakers and lots of additional home run cable. I will be using heavy duty terminal blocks in a splice box near each outlet so there will only be 1 set of wires entering the outlet box itself.
I know there are special allowances for welders so you don't have to mention that, it's not what I'm trying to get answered.
Actually I want to use 6awg for the hots to aid in voltage drop, but I would like to reduce the neutral to 8awg and the ground to 10awg. I do not want to use the conduit as a ground even it it was allowed, so don't ask.
If this were a single outlet or a fixed in place device I believe I could use wire as small as 8,8,8,10, and based on the device and unbalanced current, maybe 10awg for the neutral. Normally I wouldn't quibble about using larger conductors for neutrals and grounds, however based on my estimates, using a 8awg neutral and 10awg ground in my garage adds up to around $400 in copper savings alone.
Had an idea... Could I use 2-2-2-4 aluminum cable for the main run and splice down to 6-6-6-6 at each splice terminal block? Aluminum is sooooo much cheaper. Would that satisfy 210.24?
Brief background: I'm trying to add several 50A 250V outlets spaced around my 40X64' garage for welders or other mobile high power cord and plug equipment. Only one device is to be plugged in at a time so I want to wire all the outlets to one 50A breaker instead of 3-5 individual breakers and lots of additional home run cable. I will be using heavy duty terminal blocks in a splice box near each outlet so there will only be 1 set of wires entering the outlet box itself.
I know there are special allowances for welders so you don't have to mention that, it's not what I'm trying to get answered.
