I need some help form those experienced electricians out there with a wiring question. I am in the process of installing a residential refrigerator in my fifth wheel RV. I'm wrapping it up and ready to install the new refrigerator. I have run a dedicated 110 line to the refrigerator from the inverter. There is a single 110 outlet behind the refrigerator that is part of the RV wiring that is on a branch circuit and breaker. I would like to be able to use the outlet that is currently in place to plug the refrigerator into. My desire is to be able to install a switch on the wall beside the refrigerator to manually switch between the shore power and the inverter power. I am not sure if this can be done. I was told to buy a double throw double pole switch to achieve this but I'm very confused as how to wire it. I do not have an a/c powered inverter nor does it have an auto switch over. I would just like to switch between the two power sources using the existing single plug. I do not know if I have the correct switch but Have been told I do. I just don't know who to wire it. Please advise. Thanks, Phillip

Hot on the left. Neutral on the right.Fridge in the middle. Inverter on top, utility power on bottom.All grounds to a common bus.

You will need another junction boxThe existing wires, and the new inverter circuit will meet at the junction box and another cable/cord will run from the junction box to the out letBasically you will remove the out let from the existing boxBring your new circuit to that boxConnect both circuits to the switchBring out a wire to a New box for the out letThe switch has 6 connectionsThe output for the fridge goes on the two center connectionsThe old circuit goes on one endThe new circuit on the other end pFlipping the switch one way or the other choices circuitThis is for hot and neutralIt does not switch the ground wireMost likely wired in romex, which has a bare ground wireConnect the ground together, only the grounds, nothing elseOr do it the easy wayBuy a 15/20 amp plug and play transfer switchIt comes with an outlet and two male plugsRun your new circuit to the fridge areaPlug the transfer switch into both circuits, outlets from New and oldPlug fridge into transfer switch

Hi,It would be easy and simple to have two receptacles side by side, then wire one to the shore power, the other to the inverter. Then plug in the refrigerator to the desired receptacle.Another way is to always leave the refrigerator on inverter power, and leave it on 24/7. Then while on shore power, the charger will supply 45 - 65 amps of DC power to the batteries and inverter, powering everything. . . Using a three way switch 'might' work and 'probably' will not explode. . Yet it "CAN" short across the terminals. . . When I worked for a large city, they used 3 way switches on the lights in the radio transmitter room. One side was 'on' with generator power, the other 'on' with shore power. When they test the generator, all the lights that had been off (because they did not get power from the generator when not running) would turn on for the duration of the test. Sometimes the circuit breakers from shore power to the light switches would trip. I don't know why, my guess is a short circuit? Many times the 3 way switch will not shut off before making contact with the other wire. So if you want to chance back feeding 120 volt shore power into the output wires of the inverter, and cause it to explode, try this. . .. If you want it to be safe, then a proper automatic transfer switch, or manual transfer switch is the SAFE way to make sure that the power is off, and that the shore power will never feed into the output wires of the inverter. . Most inverters will burn up or melt something internally when 120 volts is applied to the output wires. Some will synchronize with the incoming shore power, but not many. Try the two plugs, it is safe. Try just leaving the inverter on, and let the charger feed power to it. That is safe too, not not as energy efficient.Also are you using a modified sine wave inverter or a pure sine wave inverter? Most motors require pure sine wave power, because they have high torque motors that will require PSW power, or they will tend to draw to many amps, or not start at all.Fred.

My fridge is on inverter full time, When charging my converter has enough power to do both jobsCharge batteries and supply the extra for the inverterI should have mentioned that option

Thanks to all who have replied and so quickly! The switch I purchased is rated at 30amps. I could switch the plug back and forth but I'm really trying not to have to do that. I'd like a seamless (at least at the expense of flipping a switch) way of choosing between shore or inverter power. I have thought about letting the fridge run off the inverter all the time. However, I figured it to be unnecessary wear and tear on the inverter - especially in very hot weather. I did purchase a Pure Sine Wave inverter. However, it does not have a 110 input - only GFCI outlet only. Also, I have installed a remote switch to power the inverter on and off from inside and near the 110 selector switch that I'm tiring to wire. As a precaution, I do not plan to use the 110 selector switch to switch back and forth while hooked-up to shore power. Thanks for all the input and so quickly! Much appreciated and I will sleep better feeling there is hope to wrap this up tomorrow. Thanks! Phillip

Swiching for a dedicated Refrigerator inverter | Good Sam Community

21 Replies

hawkeye-08
Explorer III
Aug 11, 2014
I like the auto transfer switch plan. Keep us posted on how this turns out..
pcm1959
Explorer
Aug 11, 2014
I have been advised to wire this switch multiple ways including the instruction above. None has worked. Either the inverter does not like the switch or the switch is bad. I have sent the switch back and have, on the way, the Xantrex 30amp auto transfer relay. Simple plug and play. Yeah. Thanks to all who contributed. Phillip
jhilley
Explorer
Aug 10, 2014
To wire the switch connect the refrigerator power to L1 and L2, the inverter power to A1 and A2 and the shore power to B1 and B2.

Leviton 1288 DPDT Switch Instructions
pcm1959
Explorer
Aug 10, 2014
smkettner wrote:
With the above transfer switch only the fridge will see inverter power. The rest of the RV is isolated from the inverter. There will be no effect on the Progressive Dynamics power management system. All systems remain protected and isolated if you have the inverter on at the same time you are plugged in.

Thanks! Ordered.
I want to thank everyone for their input and help here. We have a lot of GREAT people here willing to offer their expertise and advise to fellow RVers. Thanks again. I will update the post next week when the new fridge is installed. Phillip
time2roll
Nomad
Aug 10, 2014
With the above transfer switch only the fridge will see inverter power. The rest of the RV is isolated from the inverter. There will be no effect on the Progressive Dynamics power management system. All systems remain protected and isolated if you have the inverter on at the same time you are plugged in.
CT_WANDERER
Explorer
Aug 10, 2014
No this will not affect your power management system. Go with transfer switch that smkettner posted about will be better than using the manual switch.
pcm1959
Explorer
Aug 10, 2014
I REALLY appreciate the input from everyone. I guess I was not familiar with the transfer switch option which sure looks like a quick and easy solution. It is even cheaper than the switch that I purchased that I cannot figure out how to wire. I am starting to thing the switch is faulty!
In regard to this type of auto transfer switch, I have hard-wired Progressive Dynamics Power management system hard wired into the rig where the shore power comes into the rig. Would this trip or send an error message to the Progressive when the transfer switch makes the change. Thanks, Phillip
time2roll
Nomad
Aug 10, 2014
If you have two outlets the listed transfer switch is plug and play.

1) Look at the picture, it has three cables. The one with a plug you just push into the inverter outlet right there in the fridge compartment.

2) Put a plug from Home Depot on the other input. The wire next to the plug. Plug this into the existing outlet that supplies utility power.

3) Put a female end on the output cord(the wire on the right). (Home depot has this connector also) plug your fridge into the female connector and your beer will be cold in just a few hours from either source.

This does not power the whole RV, just the fridge. The switch will never connect the two sources at the same time so all is good. Plug and play, no worries.
pcm1959
Explorer
Aug 10, 2014
westend wrote:
This 15 amp Xantrex transfer switch would be perfect for your application.

My inverter does not have an a/c input - only output. I only want the inverter for the refrig and not the rest of the coach. Wring this transfer switch looks to be a bigger nightmare than what I'm trying to do. I already have an inverter installed, a dedicated line from the inverter and existing 110 power. All I want to do is manually switch between the two. If I can't figure it out I'm just going to have 2 outlets - one for the inverter and the existing 110 and simply move the plug from one to the other. Phillip
pcm1959
Explorer
Aug 10, 2014
BFL13 wrote:
"I don't have a genset, don't dry camp, and I'm only interested in using the inverter to power the refrigerator."

Lost me there. If you are always on shore power, why have an inverter at all? (except for that television re-boot thing some have)

Because I have to be able to pre-cool the refrigerator at the storage lot and be able to keep it cool during travel. Thanks! Phillip