I’ve got a late 1980s home that currently has 100A service. I was looking to upgrade to 200A service, so I contacted the local utility company. They sent someone out to do a site survey of my existing feeds and reported back that I have 1/0 AL conductors in a 2” conduit which makes sense and aligns with 100A service.
However, the utility planner says I can use the existing 1/0 AL feeds and just do a straight panel/meter pan swap to 200A (it’s a combo unit). I reconfirmed that the feed does not need to be upgraded and they verified and sent me a service order so that I can pull a permit to move forward with the work.
Im confused because from my research in the NEC tables, I should need to go up a bigger feed to support 200A service (3/0?). Is there something I’m possibly missing here?
I would be happy to save the dollars and go with their recommendation up to the connection to the home. From there, the NEC takes over and you may have to upgrade.
Your service will be 200amps, but that doesn’t mean your panel will be. When you upgrade the panel, then you will need the bigger SECs.
I’m not sure I follow this statement. I’m planning to upgrade to 200A panel and meter pan. Utility has stated my current SECs are allowed for 200A service.
Ok. Gotchya. I was thinking you were talking about SECs’. You are basically referring to the actual service lines from the utility. If they say what you have is big enough, than I would go with it. If you had the distribution panel inside the home, the feeders (SECs) from the meter to the panel would need to be larger than 1/0 aluminum. But the service feeders from the utility aren’t controlled by the NEC, as Brian mentioned above.
Ok. Gotchya. I was thinking you were talking about SECs’. You are basically referring to the actual service lines from the utility. If they say what you have is big enough, than I would go with it. If you had the distribution panel inside the home, the feeders (SECs) from the meter to the panel would need to be larger than 1/0 aluminum. But the service feeders from the utility aren’t controlled by the NEC, as Brian mentioned above.
In my area I own the underground lateral from the transformer to my meter pan, IMO those cables would need to be upgraded to cables rated for 200 amp service, either 2/0 Copper or 4/0 AL.
You should consult a licensed electrician in your area to verify.
The NEC begins at the service point. For an overhead service that is where the utility drop from the pole connects to the service entrance conductors. The service entrance conductors beyond the service point are bound by the NEC they need to be a minimum of #4/0 aluminum for a 200 amp service.
I’m an electrician in California. This is common. There is almost never a circumstance where we have conductors larger than 1/0 ALU for a 200A service. Some jurisdictions allow a 200A underground service with conductors smaller than 1/0.
As others have said, the power company is not bound by the NEC and do not have to comply with those conductor sizes.
