With restrictions. Smaller conductors in the same cable may be paralleled to reduce voltage drop IF the breaker will adequately protect any single conductor.
EG, Any number of 15 amp rated conductors (#14AWG) may be connected in parallel IF they are contained in one cable they are fed from a 15 amp breaker.
You may run a multi conductor cable in conduit to comply with this rule.
In the 2006 code this is rule #12-108(3).
Neutral conductors less than #1/0 AWG may be run in parallel under certain conditions, see rule 12-108(4)
Bill
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"Why not the best?"
Jimmy Carter
Just because im curious, why would you run parallel #1 cables? You're only going to get about 250A out of the deal? Plus is the motor lugs set-up for parrallel runs? You cant shove two wires into one lug and clamp it down.. Plus where are you going to find a breaker that small with duel lugs? Is is a bend radis issue or something?
jwparker, I am reviewing a design by a Canadian vendor for installation in the US and trying to determine if they were following Canadian standards. The engineer followed the vendor's design but we caught it in time and installed 1-3/0 per phase.
Thanks.
