Using a 50 AMP Cheater Box

[Bill-N-Donna]

I recently purchased a cheater box so we could run both AC's while at the stick house. Both AC's ran today for several hours and then the 30A BKR in the stick house tripped. The 20A BKR was ok. I would think that each AC would be wired on separate circuits. If so why did both of them quit running? With this set up if half of the electrical system in the camper trips does it take out everything?

A friend and myself recently installed the 2nd AC. The camper was pre-wired for it. It was a very simple installation. Could this just be an anomaly where it got so hot today and perhaps it just overloaded the 30 A BKR? I will mention that the electric water heater was also on.


I'm hoping that someone may have experienced this and can express their opinion as to what was actually going on. Does anyone have any ideas? I’m all ears. I do foresee that I will be up-grading our service to an actual 50AMP service.

Thanks for your in-put!

[DQDick]

Here's the reason we moved to a 50amp site. We could only run one AC and after that it was a toss up. There's a lot of "ghost electronics" in these rigs. In ours for instance there is always power to the DVD player and the Two TV's. Cell phone and other recharges that are plugged in will draw juice whether the device is hook up or not. Clock and weather radios etc are all nipping some juice. The battery charger picks it's own time to work. The hot water heater and the refrigerator may pick the same time to come on as the AC coming on high. Don't even think about what happens if you want to do laundry or use the microwave. Since I have an EMS system I was able to watch the draw from our rig and seldom were we less than approaching or going over 30amps and that was with us trying to stay under. When it did trip it was always the main, never the 30amp breaker for the plug. With 50 amps we run it all and it doesn't seem to be an issue. I'm no electrician so I'll leave the explanation to someone like John who knows, but my understanding is with a cheater box you still are a good deal short of a true 50amp service.

[Tom S.]

The air conditioners are on different circuits, and as you found, you were able to get by rnning both for a while. But asome point, both tried to start up again at the exact same time. Here's what happened: each unit has a 20 amp breaker because each can require 15 to 18 amps when it starts up. That means if both try to start at the same time, they are pulling a total of 30 to 36 amps (plus whatever else happened to be running in the trailer at the time, like your power invertor). That's why it tripped your 30 amp breaker.

[1retired06]

We were at a campground recently where the park staff instructed a camper to disconnect his cheater box, and either use 30 AMP or move to a 50 AMP site and pay the extra charge.

[bncinwv]

Keep in mind there are other loads on the same side as each air conditioner. I would venture to say that your converter is likely on the side that tripped. You can flip the breaker to disable it and do the same for other energized devices and you may be okay.
Bingo