i bought a wooden framed house "as is", a great deal but left me house poor. I found the 200 amp main panel is being supplied by SEU 2/0-2/0-2/0-1/0 (00-00-00-0), the run is 5 ft u/g thru 2" pvc, through the crawl space and up to the main breaker box. No that is not a typo, 2/0 aluminum wire, in a house with a 5 ton AC. Besides the obvious NEC violations, a higher priority is keeping the house from burning down.

I have a ton of Alum 4/0-4/0-4/0-2/0 SE(R), marked XHHW-2. I stripped the SER jacket and used the 3x 4/0 XHHW-2 conductors, plus a marked 2/0 alum XHHW-2 cable for the ground. Unfortunately The 4/0's dont have any markings so yes I know it wont pass an inspection. On the other hand, I believe all the conductors are correct size and XHHW-2 construction to meet the "spirit" of the code and most important prevent a fire. Its a stop gap measure until I can save up and do a proper job with copper 3x 3/0 THWN-2 and shielded ground.

So I guess Im looking for comments or criticisms on what ive done and what to do next. I am rather cash limited at the moment, so bear that in mind.

  • was the old stuff SEU or USE? (SEU is the grey jacket with the braided shield, USE is the twisted-together burial multiplex) Aug 17, 2023 at 2:50
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    old stuff is SE, unshielded. Its not USE burial. Aug 17, 2023 at 3:31
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    SEU and SER are not allowed underground. Which side of the meter is this on? If it's on the power company side of the meter, it's a big bag of Not Your Problem. Aug 17, 2023 at 4:44
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    How big is your load calculation? Even with a 5 ton AC I'd be really surprised if you're ever cresting 100 amps, well within the range of 2/0 aluminum. I'd wait to touch this until you plan to do electrical work that adds a bunch of equipment.
    – KMJ
    Aug 17, 2023 at 5:44
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    You mention a 200 amp main panel run going to the main breaker box. Is the 200 amp panel a sub panel?
    – JACK
    Aug 17, 2023 at 12:14

1 Answer 1


Emergency... priority is keeping the house from burning down... looking for comments or criticisms on what i've done and what to do next. I am rather cash limited.

  • don't run the AC
  • don't run a bunch of appliances at once
  • do a survey and get some kind of accurate idea of what your power draw in the house realistically is
  • sounds like you have access to the aluminum feeder wire, measure the temperature there with measured loads in the house to know what you have
  • having something not to code doesn't mean will catch fire and/or blow up, you likely have more fire risk elsewhere (in a new house which you haven't found yet)

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