I know this issue was covered in another thread so my apologies straight away I feel like I’m going crazy. I ran across this issue on new construction. Not something I’m inpsecting I’m just nosing aroung my neighborhood and this caught my interest. Maybe I’m just and idiot, and that’s probably the case, but the panel is rated 200, the main disconnect is 200 and the underground service entry is 1/0 Aluminum. Meter is not on but similar construction in the neighborhood is using a meter rated for 200 amps. Here’s the pic?? What am I missing besides some brain matter? Is this a PoCo issue? Even if it is, can this arrangement be correct??
It is not uncommon for the POCO to install conductors way smaller than we would use if sized per the NEC. With that said the SE Conductors should be protected at their ampacity. If they used 310.15(B)(6) then 1/0CU would be good for 175A but I would expect to see the panel OCPD not to exceed 175A.
So with that said…who actually ran the SE Conductors as usualy the POCO does not do this until after the load side of the meter has been hooked up.
So in reality the conductors from the load side of the meter to the service disconnect should be sized properly to the OCPD. If the service conductors are rated a 175A then the OCPD should not exceed the 175A in this example.
Paul, thank you very much. I’m in the middle of viewing your NACHI TV electrical inspection course which I must say is OUTSTANDING. Thanks again.
Glad you like it Michael…Enjoy !
Almost missed one your points, you mentioned 175A using copper. In this example I’m observing Aluminum, that only compounds the problem correct?
Yes…it means the SE Conductors are rate even less than we thought. Remember now we cn’t govern the POCO and what they install. We can only wait to see what is actually run to the Service Disconnect. If the electrical contractor runs in 4/0AL or 2/0CU then they would be fine…unless of course the electrical contractor ran the underground SE Conductors…then it would not be outside the scope of the NEC because it is not under exclusive control of the POCO…then we have problems.
Paul thanks again. For those of us who think we’re comfortable with electrical inspections, I would still advise you to take advantages of Paul’s expertise in the Nachi TV inspection course. Everyone can benefit to some degree no matter what your level of comfort with this topic.