#6 on 60 amp

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RETRAINDAILY

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PHX, arizona
I've got 2 pieces of equipment data sheet says 35 amp load, 50 amp OCD installed.
I've ran a 1 1/4 for 6 #6 + ECG
Now the plant has 2 60 amp 35k breakers in inventory they want me to use.

so 6 ccc 120 deg. would I need to up size to a #4
 
In one regard, I don't see a problem but it would depend on the specifics. #6 is normally o.k. for a 65 amp load, and if you need to derate 240.4(B) might even help, however, if the manufacturer's instructions call for a maximum OCP of 50 amps, you can not exceed that.
 
the equipment has 50 amp OCD in it, through the door disconnect. fused
it only has 35 amp load

After derating I come up with 49.2 amp for a #6

I can get 7 #4 in the 1 1/4 (table c.8 )so I have no problem up sizing.

I get flustered when I put wire on a breaker that that does not correspond with the breaker.

But I think I 'm good with the #6 the way I understand it.
 
#6 is good for 65 amps. If you have 6 CCC in the conduit then you must derate by 80%. That leaves you with 52 amps. 240.4 allows you to use the next standard size breaker as long as the load is not greater than 52 amps
 
Dennis Alwon said:
#6 is good for 65 amps. If you have 6 CCC in the conduit then you must derate by 80%. That leaves you with 52 amps. 240.4 allows you to use the next standard size breaker as long as the load is not greater than 52 amps
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If 90C conductors are used the starting ampacity for #6 would be 75 amps. I believe this is how the OP is getting the 49.2 amps.
 
I missed your 120?, I agree with #6 THHN you would end up with 49.2, so 50 would be would max breaker anyway (assuming all 6 are ccc)
 
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