Both ACs on same leg of 50 amp?

[Second Chance]

We spent this past week at a small city owned/operated park and RV campground in central Ohio. It was pretty warm when we pulled in and we were anxious to get the rig cooled down. As soon as I connected to the 50 amp outlet on the power pedestal, we started both ACs and went about our business.

A short time later, the 50 amp breaker on the power pedestal tripped. It was quite hot when I went out there to check it. I reset it and went back inside to the check the Progressive Industries EMS to see what the loads were. One leg was at 121 volts and pulling 5 amps. The other was at 115 volts and pulling 32 - 34 amps. While this was still less than 50 amps on one leg, the circuit breaker in the pedestal could not handle it. The park replaced the breaker the next day but the behavior persisted.

When we moved to Mohican State Park, OH, yesterday, I decided to try an experiment. I turned both ACs down far enough for them to cycle on and watched the EMS again. The loads weren't quite as high - 5 amps on one side and in the 20s on the other. Voltages were both in range. This leads me to one conclusion and one question:

1) conclusion: the first park was old and the electrician couldn't vouch for the condition of the wiring or connections that were underground. An under-voltage situation will cause appliances to try to draw more current and this overloaded the circuit breaker on the old park system.

2) question: from the readout on the Progressive EMS in both situations, it would seem that both ACs (a 15K in the living room and 13.5K in the bedroom) are wired to the same leg of the 50 amp house system. Am I assuming correctly here or completely off base? If that is the case, why would GD have done that? It seems to me that one would want to distribute the current load across both legs of a two-phase service to maximize what can be run on the 50 amp/50 amp (100 total) service. Should I see if I can rewire the front AC to the other side of the panel or am I barking up a tree with nothing in it?

Rob

[oldguy]

I've wondered why it's wired like that too. This one plus our last two fivers are the same way.

Sent from a tiny keyboard.

[Bob/OlallaWA]

If it were me, I would put them on separate sides of the panel. If you don't feel competent, have a electrician do the work.

[jkib2238]

[QUOTE=oldguy;81874]I've wondered why it's wired like that too. This one plus our last two fivers are the same way.

I just finished installing an inverter into my 337, so I had to figure all this out myself. Yes, both AC units are on the same 50a branch along with the hot water tank while on electric, and the converter. Everything else is on the other branch which includes fireplace, all outlets, AV units, washer/dryer, fridge on electric, etc. So I would say the load is fairly well balanced.
On a side note --since I installed the inverter I disconnected the converter since it's not needed. I then switched the fireplace to the branch with the AC units to try and rebalance again. The two outlets near the couch are on the fireplace circuit as well. I ran the non AC 50a branch through the inverter. This allows me to virtually run everything on that one branch with the inverter; although I wouldn't run the washer/dryer while on the inverter.
I've had no issues running both ac units at once on a 50a service along with the hot water tank, and converter before disconnecting it. You may want to check the screws for the hot wires to your ac breakers to make sure they are not loose.

[offtohavasu]

You'd have to do some load calcs for balancing. For example, is the microwave on the opposite phase, or kitchen outlets (think coffee pots), fireplace? They may have just slapped them in any old position, or there also may be some heavier loads on the other phase as well.

[Paul & Deb]

2) question: from the readout on the Progressive EMS in both situations, it would seem that both ACs (a 15K in the living room and 13.5K in the bedroom) are wired to the same leg of the 50 amp house system. Am I assuming correctly here or completely off base? If that is the case, why would GD have done that? It seems to me that one would want to distribute the current load across both legs of a two-phase service to maximize what can be run on the 50 amp/50 amp (100 total) service. Should I see if I can rewire the front AC to the other side of the panel or am I barking up a tree with nothing in it?

Rob

Mine is set up the same way (by the dealer not the factory). I asked the same question in another thread. It hasn't caused my any problems but it is certainly unbalanced.

[Second Chance]

The small city park in question was the first - and only - place we've ever had that problem. I think I'll leave well enough alone for now. Thanks, everyone.

Rob