Forum Discussion

Lurker52's avatar
Lurker52
Explorer
Mar 16, 2019

Running the residential refrigerator on the inverter

Hello,

I have a 2001 Monaco Knight DP. The previous owners installed a residential refrigerator. The rig also had a Xantrex 1500 watt modified sine inverter. The frig. was not connected to the inverter. I am in the process of upgrading to a 3000 watt Xantex pure sine inverter. I am doing this so we can run the frig. while traveling and not use the generator and maybe for some Walmart parking and some short boondocking stays.

I installed the new inverter just like the old one. The way it was installed and how I have done the new one is that the output A/C electric has 2 lines coming out of it. These operate the microwave and a few outlets and 2 T.V.
These items also are powered by the main breaker box. They switch back and forth from inverter to shore/genny power. I don’t understand how this is done. I would like the frig. to do the same thing. There is an outlet that I could get power from near the frig if I have to but I would like to have it on its own circuit.

Is there some kind of relay that switches the micro and outlets somewhere and what do I have to do so the frig work this way? I believe if I just run a secound wire to the breaker box the inverter would then have 120 volts going back into it and I think that would not be good.

Sure could use some help.

Thanks as always,
Class A
  • hohenwald48's avatar
    hohenwald48
    Explorer
    Mar 17, 2019
    Ditto what Doug said. I used to own a 2001 Monaco Knight and what he said is exactly correct. Except, on mine the outlet was labeled "Icemaker" and not "inverter".
  • Executive45's avatar
    Executive45
    Explorer III
    Mar 16, 2019
    As Doug pointed out Monaco put two receptacles behind the fridge. Plug it in the one marked inverter and you are good to go...Dennis
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Mar 16, 2019
    The big Xantrex units should have both AC in and AC out

    They have an internal switch that does the magic

    My Prosine 2.0 had that. and my New Freedom 2000 does as well.
  • wolfe10's avatar
    wolfe10
    Explorer
    Mar 16, 2019
    The vast majority of inverter/chargers have a built in transfer switch (pass through).

    So, when they receive 120 VAC IN from shore power or generator, the "pass through" that power to all circuits downstream of the inverter/charger. Receiving an external source of 120 VAC also initiates battery charging.
  • dougrainer's avatar
    dougrainer
    Nomad
    Mar 16, 2019
    You need to check and get back to this forum. Are there 2- 120 receptacles behind the refer? Monaco when the original RV refer was optioned, IF it had the optional refer Icemaker, they ran the Icemaker power from the 1500 watt Inverter. One Outlet is Inverter driven and the other is to regular Shore Power. If so, you just connect the new refer to the Inverter plug. IF NOT 2 Plugs. All you have to do is move the Refer receptacle BREAKER wire to the Inverter side of the Main Breaker panel. Doug
  • larry_cad's avatar
    larry_cad
    Explorer II
    Mar 16, 2019
    I can't confirm the Xantrex, but Magnum inverters have a 120 feed from the breaker panel into the inverter, and output(s) to various loads such as outlets. When there is 120 available from the breaker panel, it goes directly to the inverter outputs. When the 120 from the breaker panel goes away, such as when you are traveling, the inverter automatically outputs 120 from the inverter which is being powered by the batteries. It is an invisible and automatic function which takes care of itself. There is no reason to make it complicated. Let the inverter do what it is designed to do.

    The battery charger in the inverter works in a similar fashion. When there is power available from the panel, the charger works to charge the batteries. When the 120 goes away, the batteries work to run the inverter. It's all automatic. Depending on the manufacturer, the battery charger may or may not charge the chassis batteries.

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