5th wheel with 50amp service and generator connection

[gspman]

Hey all, maybe you can help understand something that i don't quite understand.

I have a 2019 couger 1/2 ton 5er with 50amp service.

I also have a generator/inverter (Briggs &Stratton q6500)
It has a L14-30 nema 4 pin twist lock 120/240vac 30am output. according to the manual the left and right pins are 120v referenced to neutral and are out of phase by 90'. Which make 240vac across left and right pins.

So i should be able to run 20.8amps on each hot side per the manual.

my question pertains to the 2 air conditioners on the roof. 13.5kbtu and a 15kbtu.

Will this generator start and run either air conditioner with this type of connection? with all other non essential breakers turned off.

guestimating that the 13.5k will surge in excess of 2500-3000 watts at start up and the 15k prolly closer to 4000 watts at startup ?

I am spinning myself in circles trying to figure this out?

Sorry if the post is too long
Scott

[Skippy38]

I have a 50amp coach also and use a Harbor Freight Predator 3500w generator.
Lol...don't worry it really isn't that hard. Per my video below, your generator should run almost everything although not all at the same time. You should have no problem starting either of your a/c units but not both at once. you may not be able to run the microwave and the a/c units together either. You just have to experiment a little to see what you can run. I hope my video below gives you some idea of what you can run...

https://www.youtube.com/watch?v=0RLujDP18Jg

[flynaz]

I have a Champion 3400 DF ((3100) and I also wired a 50 A twist connector and jumped the two phases so both are fed via the 30 amp plug from the gen set. The ac units were each on a different phase so only one worked before I jumped the 50A connector. I can start and run either AC unit when using the gen set @ 30A!
We still need to watch what we are doing, (not to exceed 30A) when running just 30A, either genset, or a 30Amp hook-up ! Hope this helps...

[gspman]

thanks guys... Skippy38, very nice video, did i see a grounding plug in the front of that genset? I didn't have one of those last fall when i last tested

[Frank G]

Scott, If your unit is properly connected to the generator, you will be able to start and run both A/C units at the same time if the generator specifications you gave are correct. You may have to make up the adapter plug/receptacle as it may not be commercially available.

The A/C units in your (all) RV's are protected with 20Amp circuit breakers. One on each leg. You have 20 Amps available on each leg so you should be good to go. The circuit breaker on the generator will let you know if you exceed power limits.

There is a A/C unit on each leg. If you only run 1 A/C unit you have 20Amps on the opposing leg to power whatever stuff is powered from the opposing leg. Consult the power distribution box in your unit.

[gspman]

thats the missing piece of info, i didn't know... i hoped that they would have each air conditioner wired to there own leg/phase..
i tried it last fall just before i had to winterize.. didn't have have the grounding plug then...but i have one now

[Frank G]

Now that you understand how the 50 amp 2 phase (leg) wiring works, lets look at what happens when you plug into a 30 amp single phase receptacle at the campground using a "dog bone". The "dog bone" is that short adapter you purchase at the RV store with a 3 prong (30A) plug on one end and a 50A 4 prong receptacle on the other end. Internal to the "dog bone" is a jumper wire connecting both hot legs together (on the out going 50 amp 4 wire side), thus sharing the same 30Amps with both sides of the distribution panel in the RV. This is why you cannot run 2 A/C units off a 30Amp single phase circuit. You are also very limited to what other stuff you can run with 1 A/C running as you only have 10 amps left.

In (115/230 volt) RV wiring there is always a ground wire (green), Neutral wire (white) and the power wire(s) are black or red.

On the surface it appears there is only a 20 amp difference from plugging into a 30 amp 3 wire outlet verses the 50 amp 4 wire outlet. Nothing could be further from the truth. There is a 70 amp difference. With the 50 amp double phase (leg), you have 50 amps available on each leg for a total of 100 amps @ 115 volts.

I hope this is helpful to you and others, I tried to keep it as simple as I could.

[xrated]

Hey all, maybe you can help understand something that i don't quite understand.

I have a 2019 couger 1/2 ton 5er with 50amp service.

I also have a generator/inverter (Briggs &Stratton q6500)
It has a L14-30 nema 4 pin twist lock 120/240vac 30am output. according to the manual the left and right pins are 120v referenced to neutral and are out of phase by 90'. Which make 240vac across left and right pins.

So i should be able to run 20.8amps on each hot side per the manual.

my question pertains to the 2 air conditioners on the roof. 13.5kbtu and a 15kbtu.

Will this generator start and run either air conditioner with this type of connection? with all other non essential breakers turned off.

guestimating that the 13.5k will surge in excess of 2500-3000 watts at start up and the 15k prolly closer to 4000 watts at startup ?

I am spinning myself in circles trying to figure this out?

Sorry if the post is too long
Scott

Just for clarification purposes, the two legs of 120 volt hot leads are 180 degrees out of phase with each other.....not 90 degrees. It is what is know as Split phase and is exactly like the power coming into your house. The transformer secondary winding (and there is only one of them) is center-tapped with the neutral wire, effectively making two electrically separate winding that are 180 degrees out of phase with each other.