does this hurt

Options
2»

Comments

  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Options
    Re: does this hurt

    Well, not knowing the power levels involved, you might be able to get away with a toggle switch, -- DPDT with a current rating above that of the genset or Inverter, which ever is greater.

    Connect the AC loads/load-center to the center terminals, and the inverter AC outs to one side, and the genset AC outputs to the other side. Perhaps mount the switch in box designed for a light switch or outlet etc. Would not be code in most locations, but should help protect the hardware. YMMV, Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,448 admin
    Options
    Re: does this hurt

    You always hurt the one you love. :cry:

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rake1
    rake1 Solar Expert Posts: 173 ✭✭
    Options
    Re: does this hurt

    Vic I have a 20 amp switch now one on the gen one on the inverter they work great as long as you remember to turn one off and one on both on and you get a blown inverter. Or in my case two blown inverters, stupidity yes, but when you are jumping back and forth between the two sometimes you forget to turn off one switch. Chris I like the idea you mentioned that takes stupidity out of the question I have a few electrician friends I will ask about this.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,448 admin
    Options
    Re: does this hurt

    You should (really must per code) use a "Transfer Switch" to prevent both power sources from energizing the same circuit (and back feeding each other/causing damage/smoke/etc.).

    There are nice/simple "automatic" transfer switches:

    wind-sun_2237_12392720

    And manual transfer switches (like this one with two breakers and an interlock):

    wind-sun_2238_12100841

    There are also very expensive transfer switches that can autostart/cycle a genset once a week, etc... Not cheap or simple to install/configure.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • rake1
    rake1 Solar Expert Posts: 173 ✭✭
    Options
    Re: does this hurt

    Thanks for the info bill
  • BB.
    BB. Super Moderators, Administrators Posts: 33,448 admin
    Options
    Re: does this hurt

    There manual multi-source transfer switches too (marine--generator, inverter, shore power), and there are multi-circuit transfer switches too (I use one like this on my home--I can use a small genset and choose which loads to power with my smaller backup AC genest).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • ChrisOlson
    ChrisOlson Banned Posts: 1,807 ✭✭
    Options
    Re: does this hurt

    You can also get a transfer switch with real contacts in it for not a lot more money than the cheap ones. Ours is a Ronk 7205A, 200 amp, and will handle 20,000 amps RMS symmetrical surge, and it was about $570. But they also make 100 amp versions of it for about $250. We put the big switch in because we bought a 45 kVA Cummins diesel co-gen unit, but don't have it installed yet:

    Attachment not found.

    This is an example of a 100 amp SquareD QO LoadCenter with dual 60 amp interlocked breakers, used to transfer our biggest 240 volt loads (range and water heater) from the inverter to the generator, while leaving all the 120V loads on the inverter:

    Attachment not found.

    --
    Chris