NEC 2008 said:230.79 Rating of Service Disconnecting Means.
The service disconnecting means shall have a rating not less than the calculated load to be carried, determined in accordance with Part III, IV, or V of Article 220, as applicable. In no case shall the rating be lower than specified in 230.79(A), (B), (C), or (D).
(A) One-Circuit Installations. For installations to supply only limited loads of a single branch circuit, the service disconnecting means shall have a rating of not less than 15 amperes.
(B) Two-Circuit Installations. For installations consisting of not more than two 2-wire branch circuits, the service disconnecting means shall have a rating of not less than 30 amperes.
(C) One-Family Dwellings. For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes, 3-wire.
(D) All Others. For all other installations, the service disconnecting means shall have a rating of not less than 60 amperes.
Dennis Alwon said:I had not thought of what Marc has mention but also take a look at 230.79.
mdshunk said:Yes, and that wire size is dictated in large part by the chart that shows the acceptable gauges for the terminals on the load side of the meter can.
augie47 said:That's certainly the situation in this area. We have a lot of Cable TV service boxs with a SP 15 OCP and a #4 (socket minimum) service wire.
ElectricianJeff said:I recently replaced the service to the lighted entrance to a older subdivision here in town. The existing 2 circut load was connected with #12 thwn from the meter. The service entrance conductors where #12 also underground from the pole located about 10' away and 15' up.
I calculated the total load at less than 12 amps and upped the wire to #10 and protected it at 20 amps. No inspection was required and the POCO reconnected it with no questions.
Where would I find the "socket minimum" of a metercan? It didn't "feel" right at the time putting the #10 under the lugs of that 100 amp. can.
Yeah, I've seen that a few times on some of the older billboards I work on. They'd normally skin the conductor three times too long, then fold it over three times to make it thicker for the lug. Not right, but better than a single #12 or #10.ElectricianJeff said:I used the logic that if the POCO ran #12 on the line side than they would love my #10 on load side.:smile: But it just didn't feel right at the time.
mdshunk said:Yeah, I've seen that a few times on some of the older billboards I work on. They'd normally skin the conductor three times too long, then fold it over three times to make it thicker for the lug. Not right, but better than a single #12 or #10.
bth0mas20 said:I need to install a meter from the power company and feed only a well pump.
Is their a min code for the size of wire that I can feed from the power meter to the main breaker panel that will be inside the shed 7ft away from the shed?
I think you are correct but what is the code section that was violated? It is just a single conductor so is this a violation of the intent of the code (I don't think 110.14(A) is violated)? Is it a violation of "workmanlike" in section 110.12? Perhaps a violation that 90.4 can handle although, in my opinion, the AHJ should never use this section. :-?mdshunk said:. . . They'd normally skin the conductor three times too long, then fold it over three times to make it thicker for the lug. Not right, but better than a single #12 or #10.
110.3(B). A 100 amp meter can, for instance, normally lists #6 as the smallest permissible conductor. A #12, no matter if it's folded over enough times to be as thick as a #6, is still a #12 conductor.charlie said:I think you are correct but what is the code section that was violated?
charlie said:I think you are correct but what is the code section that was violated? It is just a single conductor so is this a violation of the intent of the code (I don't think 110.14(A) is violated)? Is it a violation of "workmanlike" in section 110.12? Perhaps a violation that 90.4 can handle although, in my opinion, the AHJ should never use this section. :-?