Separate electrical circuit for second A/C

[rweis]

I have a 2014 35' Laredo with 2 roof A/C. To run both A/C I had to have 50 amp service. A lot of FL state parks only have 30 amp and a separate 20 amp GFI.

I put 2@ 20 amp individual wall (roof) plug in (female), one wired to the RV electrical system, the other a separate 10/3 new circuit that terminates at the road side storage box access. Buy or make a 10/3 extension cord to go from the storage box access to the site power pedestal.

Open the bottom shroud frame of the A/C unit. Put in a 2' length of 10/3 to the A/C unit electrical system with a male plug.

Have 50 amp pedestal, plug A/C 2' plugin into the RV electrical plug in the roof.

Have only 30 amp and a 20 amp GFI on the pedestal, plug A/C 2' plugin into the separate new circuit in the ceiling and of course from the street side storage access to the pedestal 20 amp GFI.

Now you can camp in older parks and run both A/C's without any issue and not a "cheater" plugged into the adjacent site electrical system.

Task:
1. disconnect RV electrical from A/C shroud
2. create 2' 10/3 extension cord wired into roof A/C and terminated to a 20 amp male T plug
remove existing roof A/C electrical box
3. install new 2 gang electrical box. I added side wood blocks glued to space between ceiling and roof of RV to stabilize new electrical box.
4. wire existing RV electrical to 20 amp T plug female single receptacle closest to A/C
5. extend new wire from second new 20 amp T plug female single receptacle (furthest from A/C) across ceiling to front closet, down closet to storage compartment, across to street side storage access door terminate to a 20 amp T plug male.
6. Obtain 50' 20 amp T plug (both ends) extension cord. One end (male T plug) plugs into 20 amp female T plug receptacle on pedestal, other end 20 amp T plug female plugs into the 20 amp T plug male you terminated at the street side storage box access door.

[TallEddie]

I plan on doing a similar thing to my trailer next spring. I only have one A/C, but my 303TG is pre-wired for a second A/C.

My plan is to put an inline transfer switch in behind the breaker box.

The output of the transfer switch will connect to the wiring that runs up to the second A/C. The wire coming from the breaker for the second A/C will connect to one input of the transfer switch. I will add a 12/2 wire under the RV that will go from the other input of the transfer switch and terminate at a power port. Then I can run an extension cord from the power port to the 20A campsite power.

When I have 50A service, I will leave the breaker on, when I only have 30A, I can turn off the breaker, and hook up the extension cord.

[rweis]

I did mine a little more mechanical.

I put in a double gang box in the ceiling at the second A/C (front in my case, prewired for the 2nd A/C). One female plug connects to the RV wiring, the other female plug connects to the 10/3 I ran forward above the ceiling, into the storage closet, down to the street side storage access terminating with a male plug.

When I want to run separate A/C circuit, I move the ceiling plug to that female, and plug in the extension cord to the plug at the storage access door.

I did add a 2' pigtail to the A/C 120 volt when I disconnected the RV 120 volt from the A/C. That pigtail is basically "the switch" from RV 120 volt or pedestal 120 volt.

I like to make it as mechanical as possible for fewer breakdown possibilities.

[TandE]

Any pictures of the install?


Travis

[PerryB]

Get an A/C volt meter and check voltages. I think you might cringe when you see what happens with both units running.

[shane772]

I understand for the most part what's going on here and have wanted to do something similar. Wish these had pictures . . .

[Bob Landry]

I added a second 30A service. Just about all of the parks we use have 50A service, so I run two 30A shore power cords off of a breakout box plugged into the 50A outlet. I added a Blue Sea breaker panel for the second service and split the loads so that the inductive loads remained on the original power panel which is protected by a Progressive Industries EMS. The Blue Sea panel has a lockout so that the two inputs can not be shorted together. I can run two separate 30a services or I can throw a breaker and have everything run off of a single 30A service which is the original configuration.
In addition, I also added a 20a inlet that feeds two independent outlets. During cold weather, I can run space heaters from these two outlets and I don't have to shut down anything because of high current draw. All total,I have 80A of available service, not as good as 50A, but everything works.