Underground Service

[Jasonappignani]

I just became a new contractor in the state of SC. I need to install a 400a single phase underground service and I have been researching in the code using 4/0 copper. Do I need to communicate this with SCE&G also?

 

[Ponchik]

I am not from SC but my guess is "yes" you need to communicate with your power company.

BYW, welcome to the forum.

 

[jumper]

I just became a new contractor in the state of SC. I need to install a 400a single phase underground service and I have been researching in the code using 4/0 copper. Do I need to communicate this with SCE&G also?

4/0 copper is only good for 230 amps. Is this going to be a parallel install? 2 x 230 amps?

 

[mwm1752]

Generally the POCO would require a load calc and would have a min wire size for specific type services

 

[Iron_Ben]

I just became a new contractor in the state of SC. I need to install a 400a single phase underground service and I have been researching in the code using 4/0 copper. Do I need to communicate this with SCE&G also?

I believe so. At the poco where I worked we owned the wire in the pipe feeding the meter. So we had the electrician install the conduit (2" for 200 amp and 3" for 400 amp, typically). We then supplied and installed the conductor. For 400 amp services we usually used 4/0, but sometimes we used our largest, 350 MCM URD triplex. Those are both aluminum, by the way.

 

[GoldDigger]

I believe so. At the poco where I worked we owned the wire in the pipe feeding the meter. So we had the electrician install the conduit (2" for 200 amp and 3" for 400 amp, typically). We then supplied and installed the conductor. For 400 amp services we usually used 4/0, but sometimes we used our largest, 350 MCM URD triplex. Those are both aluminum, by the way.

Did you ever use parallel conductors for long runs? Or was that not in your standards book?

 

[jumper]

I believe so. At the poco where I worked we owned the wire in the pipe feeding the meter. So we had the electrician install the conduit (2" for 200 amp and 3" for 400 amp, typically). We then supplied and installed the conductor. For 400 amp services we usually used 4/0, but sometimes we used our largest, 350 MCM URD triplex. Those are both aluminum, by the way.

Those sizes may be fine for a POCO, but if the OPs install is under the NEC it ain't gonna fly.

 

[growler]

I just became a new contractor in the state of SC. I need to install a 400a single phase underground service and I have been researching in the code using 4/0 copper. Do I need to communicate this with SCE&G also?

I would contact the power company because they may furnish the cable and install it. If this is residential they may use direct burial cable and not want conduit ( they are the one's that do any repairs). Not only that but they may bore it and not trench it.

Whatever plan you come up with you need to be on the same page as the power company.

 

[Iron_Ben]

Did you ever use parallel conductors for long runs? Or was that not in your standards book?

Yes, but not often. I recall a 10,000+ sq foot mansion, all electric. We CT metered it, and pulled parallel 350's in two 3" pipes. Going by memory I think the max current draw on it was 350 or so amps.