Service panel upgrade or sub-panel

newenergy
newenergy Solar Expert Posts: 291 ✭✭✭✭✭✭
A 100 amp service panel is full. I'm hoping to install a 3kw system. Cost is a bit of an issue. The clients are pretty conservative on their power use.

A service upgrade is probably best, but it has also been suggested that installing a sub-panel and using it for a larger circuit from the house (to free a space for the sub-panel feed) and the breaker that leads to the inverter would be acceptable.

I'm leaning towards the service upgrade and will probably do it even if the extra cost comes out of my profit, but what do you think?

Comments

  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: Service panel upgrade or sub-panel

    Go with the upgrade. It will have to be done sooner or later, plus gives one less item to fail inspection.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Service panel upgrade or sub-panel

    1) what does code require in your area?

    2) whats the difficulty in changing the panel (brick, stucco, wood ?)

    3) what does code say about a sub panel - permissible ?


    I'd for sure, wire the inverter into the main panel, and split loads off to a sub-panel.

    It's not just buying a new box, but how hard it it going to be to stuff it into the place where the old box was ?
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  • newenergy
    newenergy Solar Expert Posts: 291 ✭✭✭✭✭✭
    Re: Service panel upgrade or sub-panel

    mike,

    1) It's hard to find something in the code allowing for something. Only the disallowing parts are in there. I don't know either way would be a violation and the person who recommended a subpanel has done it on installations and it has passed inspection.

    2) It's stucco and there's room for either a sub or a larger panel.

    3) Oh yeah, that's in 1)

    Another thing that could possibly be done is replacing several of the existing breakers with piggyback breakers to make room. As far as code goes for this, I think I need to look more into the panel and make sure it's not being overfilled if that is done.

    Anothing thing is, they want to add another circuit or maybe even 2 for an electric gate and some outdoor lights.

    I know it really sounds like they need a new panel and that's probably the way it'll go, but their budget is pretty fixed and I'm almost sure they'll be installing the solar either way, so it's kind of like I'm paying for their panel upgrade.

    Well, I don't want to do bad work, so unless someone tells me something like "piggybacking or a subpanel is obviously the way to go" I'll tell them they need the service upgrade. If I'm not willing to make less money, I'll have to make the bid for a couple less solar panels.