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Posted By: Sparks30 Generator - 09/16/06 12:24 PM
Having a bad morning,what is the wire size for 50 amp generator. Told the H.O 6-3. Doesn't want to pay. He already has 8-3 ran from previous install of portable. Thanks
Posted By: iwire Re: Generator - 09/16/06 12:49 PM
If it is 8/3 NM than it is rated 40 amps because of 334.80

If was 8/3 MC or 8 AWG in conduit it would be rated 50 amps.
Posted By: Sparks30 Re: Generator - 09/16/06 01:13 PM
It is 8-3 NM thats why I told him that.
Posted By: JJM Re: Generator - 09/16/06 05:10 PM
Even #6 AWG is STILL inadequate.

Conductors for standby generators need to be sized not less than 115% of the generators nameplate rating: NEC 445.13. In this case 50A x 115% = 57.5A, so you need to go with #4 AWG minimum in this application.

Joe
Posted By: iwire Re: Generator - 09/16/06 05:22 PM
Joe that is a good point.

However I believe Sparks gave us the breaker size which is not the same as the generators rating.
Posted By: Sparks30 Re: Generator - 09/16/06 07:35 PM
I forgot about the 115% rule. The genorator is rated at 50 amps. It's been awhile since iv'e installed one. It is going to be one of those Bryant all-in-one setup. The only proble is that where he wants it is about 40' away. And he wants to try to reuse what he has. Thanks again Sam

[This message has been edited by Sparks30 (edited 09-16-2006).]
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