inverter off mx-40

I was thinking it would be really sweet to run my inverter off my diversion to run my fridge during the day. Can anyone see a problem with this? The inverter would stay at the 'on' position and the mx-40 would turn it on and off with full charge only. I am not grid tied. Thanks.

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: inverter off mx-40

    The problem is the start up, the amount of power present at your diversion load, will not be "unlimited" and when the inverter tries to crank the fridge motor over, it will consume all power, and shut down. Maybe 20 times a minute till something blows.

    It all depends on how much power is at the load terminals, if you have 6KW at 24V, it would likely work. If you have a 2KW array @ 12V, the inverter will likely choke as it can't get enough surge power to start the fridge.
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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: inverter off mx-40

    if you have that much leftover power to have it diverting most of the time, i would suggest taking the power straight from the batteries then and be done with it. you are diverting x amount of power right now into nothing and it seems like a waste to even divert it then.
    do note that you are either talking about an mx60 or a c40 for the controller as there is no such thing as an mx40 that i know of.
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: inverter off mx-40
    I was thinking it would be really sweet to run my inverter off my diversion to run my fridge during the day. Can anyone see a problem with this? The inverter would stay at the 'on' position and the mx-40 would turn it on and off with full charge only.
    Assumptions:

    1) Your inverter and battery bank are large enough to handle the fridge’s load
    2) Your controller is an MX-60 (there’s no MX-40)

    Technically, this can work. Once the MX-60 has completed charging the battery bank, it switches from ABSORBING mode to the FLOAT mode. The MX’ AUX function includes a FLOAT feature that activates the AUX output only when the controller is operating in FLOAT mode. You could use this feature to activate a 12 VDC relay (mechanical or SSR) that in turn turns on the inverter and then transfers the fridge load from the grid to the inverter.

    Some Exeltech inverters include remote ON/OFF switching.

    See: http://store.solar-electric.com/exxp12vol11w.html
    And: http://www.exeltech.com/ex_root/ex_literature/xp600_1100_manual_6_23_2005.pdf

    Note: The start up load on the full batteries will cause their voltage to drop. It’s possible that the drop could be long and/or severe enough to make the MX switch back to ABSORB mode from FLOAT mode. This wouldn’t be of any use to you. Accordingly, you might try applying the inverter and fridge load manually to the batteries while the controller is in FLOAT mode and see what happens.

    HTH,
    Jim / crewzer