PV & house in construction: mixing AC and DC?

al128 Solar Expert Posts: 65 ✭✭✭✭
Hi there,

I have a general Q.

lets assume a house is being newly built and you plan to install a PV-system.

Would you have to make 2 different electric circuits in the walls (one grid-AC and one PV-DC/AC'd) ... or would you "splice" one into the other after the inverter?

(I seem to have found some switchboxes that allow you to use "either-or", but not both) but I am not really sure about this stuff




  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: PV & house in construction: mixing AC and DC?

    If you have to ask, then dont' do it, till you have learned some, and don't need to ask.

    I have to be harsh - this can be LETHAL if you make a mistake.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
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  • Brock
    Brock Solar Expert Posts: 639 ✭✭✭✭
    Re: PV & house in construction: mixing AC and DC?

    If you are going to run DC lines make sure they terminate in an alternate location and make sure they are obviously different cables from the 120vac lines.

    As Mike said if you’re not sure I wouldn’t recommend it as it could burn down your place or worse and none of us want that.
    3kw solar PV, 4 LiFePO4 100a, xw 6048, Honda eu2000i, iota DLS-54-13, Tesla 3, Leaf, Volt, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • al128
    al128 Solar Expert Posts: 65 ✭✭✭✭
    Re: PV & house in construction: mixing AC and DC?

    Just to clear things up ... I am NOT debating running (mixed or separate) ac and dc wiring in the house.

    The house will only have AC wiring, and outside the house there would be some A - B switch, with A being "grid" and B being "PV". Something like an inverted transfer switch, as I would like to run on PV power and only use the grid as backup power source (normal transfer switches are the other way round).

    In this case I assume that the wiring would be shared w/in the house (please confirm anybody) ... as A and B are mutually exclusive) - btw what is this A - B switch called technically???

    makes more sense now? - sorry for any language mixups :blush:

  • nigtomdaw
    nigtomdaw Solar Expert Posts: 705 ✭✭
    Re: PV & house in construction: mixing AC and DC?

    If your house build warrants an inverter charger suitable to run a complete house lets say 2-3 kw upwards then its quite simple. Wire yor house for normal AC loads and equipment (cool equipment and cost savings). The Dc side is responsible for transmitting solar power and some forms of wind and hyro power to your batteries. Adding a dedicated DC supply to your house above a nominal 12 volt system will only add cost after investing in a substantial dc ac converter system. Go with the flow spend your money on a quality dc to ac conversion system then reap the benefits of cheaper energy compliant AC white goods

    Did I repeat my self sorry but HTH

  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: PV & house in construction: mixing AC and DC?

    Yes you can. I have some AC lines that are switched from the grid to inverter when the sun is out and batteries are charged. I have those wires a different color from the rest. Also, the outlet covers are a different color.

    A different color is not needed, but makes it easier to find what line are on the inverter. The different color wall plate is to remind me not to plug something that will overload the inverter.

    These lines may need a sub-panel depending on size of inverter and the inspector/electrician.

    Your title is what is confusing the other posters.