0

NEC2020 230.85 requires me to put an outdoor emergency disconnect in when I'm building my home workshop. The current meter is on the house (and must be replaced), so we're moving the meter to the shop and reusing the buried wire to feed the house from the shop. I can put the emergency disconnect (must be service rated for >150A, breaker or disconnect, fusible or no) on either end of the buried line, but since I must remove the meter on the outside of the house anyway, that's the obvious place to put it- in place of the meter. I also already have the new meter socket (which are hard to find right now), so sourcing a meter disconnect combo box would be tough at this point, and I'd have to get a junction to put where the meter is now anyway. Trouble is, all the >150A disconnect boxes I'm finding are huge. The space on the corner of the garage it's going isn't very big. Both my old and new meter panels are ~13Wx19H - disconnect boxes seem to come in around 18Wx25H! The smallest thing I can find is those post type service breaker boxen that are narrow but still around 26 inches high. There's so much empty space in the boxes, why is this? Anyone know of something smaller? That isn't many hundreds of dollars? Is there any such thing as removing the guts from my old meter socket and installing a breaker in there? Garage Exterior

5
  • I take it you're using NEC 230.40 Exception 3 to have a 3-wire run of service-entrance conductors from the meter on the shop to the disconnect on the house? Commented Jul 23, 2021 at 3:55
  • Yes, that's correct.
    – Eric
    Commented Jul 23, 2021 at 5:35
  • 1
    Why is it that the space is so constrained? Perhaps a couple of photos would help? Commented Jul 23, 2021 at 11:24
  • 1
    Pic added. Some of these might physically fit, but lining them up with the existing conduit might not be possible. I did realize that I might be able to lose that 90 deg j box and pop the wires right in the back of a new panel, while cutting the vertical conduit to length for the bottom of the panel, which would give me more room/flexibility. I'm worried with a tall box, the existing buried wires might not be long enough to reach the top/line side of the breaker or disconnect, but maybe cutting that conduit shorter would solve that too.
    – Eric
    Commented Jul 24, 2021 at 2:11
  • What's in the box to the bottom right of the meter socket? Commented Jul 25, 2021 at 5:31

1 Answer 1

4

You're taking the requirement too literally.

Code does not require a "Disconnect switch that is exactly and only a disconnect switch and nothing else". Code requires anything that you can throw that will turn off power, and it's near the meter.

A literal disconnect switch is rarely used, and so it's an expensive way to do that. Common methods include:

  • Meter-main
  • Discrete meter + discrete main breaker
  • Discrete meter + "ranch panel" (main + 8 space + thru-lugs)
  • Meter/main/ranch panel combo
  • Meter/main/full panel combo

Right now you're living the "fallacy of sunk costs" - you've bought a meter that was probably not a good fit for your needs, and now you're trying to maneuver things so you can keep that from being a mistake. That is probably a waste of your time. It's definitely in conflict with your goal of a minimum physical footprint for the equipment.

4
  • Harper, you're right of course, any of those methods would work just fine. I'm happy to return it and install something else, but that leaves me with a) finding one of the items you mention, that's Xcel Energy compatible (they have pretty stiff requirements for their meter panels) and b) I'd still have to find a j box to replace the existing meter panel to splice those wires in, and those look to be a couple hundred. If I can find a breaker or disconnect that fits where the existing meter is for, say $150, I'm in $300. If I find an Xcel compatible breaker main, like the Eaton...
    – Eric
    Commented Jul 24, 2021 at 2:25
  • ... MBX816B200BTS they are using at the development down the road (and that's a big if right now), plus a j box for the splice, I'm in for at least $600. Not a big deal, and that might be just what I'll have to do (your advice is sound). But if I can stumble on something that fits here it simplifies things a bit.
    – Eric
    Commented Jul 24, 2021 at 2:25
  • @Eric -- can you tell us what's in the box to the bottom right of the meter socket in your photo, please? Commented Jul 29, 2021 at 1:23
  • That's an old POTS termination block that I'll be removing.
    – Eric
    Commented Jul 30, 2021 at 13:45

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.