Can I power 1 leg of a 240v single phase panel?

Thick8
Thick8 Registered Users Posts: 49 ✭✭
My inside panel has 240v single phase coming in (L-L-N). My stove and electric car plug use 240 volts, so they draw power from both 120 volt legs. I would like to install an inverter for automatic battery backup on the 120 volt leg that powers "essential" circuits. Is this possible to do without having to relocate the 240v circuits?
Thanks.

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    You will have to remember to Never Use 240 appliances, and maye for safety, switch off their breaker when you run off the inverter.

    Another possible issue, is overloading the neutral wire since there is no other phase to equalize the power. Maybe someone else can explain it better than I.
    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 ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Thick8 said:
    I would like to install an inverter for automatic battery backup on the 120 volt leg that powers "essential" circuits. Is this possible to do without having to relocate the 240v circuits?
    Well, yes... Sort of.

    I think the easiest way around would be to run a 120v sub panel right next to your main, with all the loads you believe to be essential. Connect it to the main panel through a transfer switch, You may even be able to use an inverter pass through as your transfer switch, that would automatically charge your batteries and transfer the loads when there was a failure.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    There is a way to install a transfer switch to power just the 120 VAC (or 240 VAC) circuits... Here are a couple from Home Depot:

    https://www.homedepot.com/p/Reliance-Controls-30-Amp-10-Circuit-Manual-Transfer-Switch-310A/206499407?MERCH=REC-_-searchViewed-_-NA-_-206499407-_-N&
    reliance-controls-transfer-switches-310a-4f
    You basically connect to your main panel. Disconnect a branch circuit and wire "to" the transfer switch. Then wire the same circuit from the transfer switch to your disconnected branch circuit with a wire nut.

    I did this with my home... But I got a 6 circuit version--And I really needed more circuits for backup connections.

    You can use the "single" generator connections to connect to an AC inverter+Automatic transfer switch pretty easily... And just leave the above transfer switch in "Genset" position--And let the Inverter/AC transfer switch combo power the above transfer switch as needed. And you can always bypass the inverter to utility power by switching back to normal.

    There are quite a few different version of this boxes.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset