NMC is rated for its 140 degree amperacity, regardless that it is actually
190 degrees insulation; so #8 copper used to feed a subpanel needs a 40a
#6 can have a 60a breaker because it is 55a and rounded up to the nearest
I want 50a capacity, so I need #6.
Is this correct? Just want to be sure.
For the benefit of those who may not know... wire and cable are
temperature-rated in degrees CELSIUS. NM is rated at 60 degrees C. Toller is
referring to the Fahrenheit equivalent.
BTW, it's "ampacity".
You sure about that? (90 C = 194 F, BTW)
Yes, it is. Make sure you use a 4-wire cable, and keep the neutral and ground
*separated* in the subpanel.
Doug Miller (alphageek at milmac dot com)
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