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Posted By: RickG Small commercial services - 06/20/03 11:15 AM
As far as the NEC goes, is it permissible to install 4/0 al service entrance conductors to a non dwelling service consisting of only 1 service disconnect? I thought that the minimum was 250 MCM al for this type of service. So many electricians seem to think that 4/0 is OK for 200 amp commercial. I am looking for other opinions & code references. Thanks,
Rick
Posted By: Ron Re: Small commercial services - 06/20/03 02:04 PM
Table 310.15(B)(6) can only be used for dwellings. A 200A commercial service must be from table 310.16, 250 kCMIL AL minimum.
Posted By: engy Re: Small commercial services - 06/20/03 08:45 PM
4/0 Al 75deg is rated at 180A
Round 'er up to 200A.
4/0 must meet article 220 load calc.
Posted By: iwire Re: Small commercial services - 06/21/03 12:39 AM
240.4(B)Allows us to round up to the next standard size breaker under 800 amps.

Before doing this read the article yourself to see if you meet the 3 requirements.

For this service you should be all set.
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