50 amp coach on 30 amp power

[Grey_Mountain]

We are currently in a 30amp site. As we use various electrical components, the "brain" will show us how many amps are being used. What happens if we exceed the 30 amps available? Say, two small heaters that will use 15 amps each all by themselves. The fridge, of course, is always on and pulls a few amps.
We are very inexperienced in using 30amp only in this coach, although our former gasser was a 30 amp rig.

Thanks.

GM

[wolfe10]

theoldwizard1 wrote:
Some of what happens may depend on how your 50A to 30A adapter/cord is wired. There are two choices.

• It may be wired so that one "leg" is completely ignored. If wired this way one of your AC and possibly some of your outlets will not work
• If both legs are wired together, the worst case is that you will trip the breaker at the pedestal. You might even be able to run both AC units simultaneously (as long as they don't start simultaneously) or run both of your heaters

I have never seen a 30 male to 50 female where the one hot on the 30 was only wired to ONE hot on the 50 amp side.

Said another way, a "proper" 30 to 50 always connects the single hot on the 30 amp male end to both hots on the 50 amp female end.

Would love to see a link to one wired any other way!

[theoldwizard1]

Some of what happens may depend on how your 50A to 30A adapter/cord is wired. There are two choices.

• It may be wired so that one "leg" is completely ignored. If wired this way one of your AC and possibly some of your outlets will not work
• If both legs are wired together, the worst case is that you will trip the breaker at the pedestal. You might even be able to run both AC units simultaneously (as long as they don't start simultaneously) or run both of your heaters

[time2roll]

Heater is probably 12 amps not 15. I agree it would help to run what you can on propane or you could be in the dark. If you do choose to run near the max keep an eye on the 50/30 adapter as they are known to overheat if the connection is less than perfect.

[BB_TX]

Simple answer is it will trip the park breaker but will not harm anything. Just reset the breaker and remember what you were using at the time and don’t use that combination any more.

[Cummins12V98]

"YOU" choose what you use by watching amps used for each item on your meter. Don't exceed 30A and all is well.

[swphotobug]

You don't say what coach you have. Ours is a 50a that runs fine on 30a. We have a system that sheds loads as other components need electricity. An example is the A/C's. Only one will run at a time when shedding. Our coach is a 2015, if yours is newish check to make sure you don't have load shedding. Other than that you will quickly learn what combination trips the breaker. We have all our electic items labeled with how much each takes. We bought a Kill-A-Watt and measured everything.

[rhagfo]

Well depending out side temps you could get by with one heater, or just use your furnace.
That said if you excede 30 amps you will likely trip either the the Post breaker, or the main in your coach.

[accsys]

If you exceed the 30 amps the circuit breaker on the pedestal should pop and shut off power to the coach. If we are on a 30 amp site we switch the water heater to propane only, set the inverter/charger to only use 5 amps to charge the batteries, and set the reefer to propane only (if it's an absorption type). This will allow more power to be used on other items without popping the breaker on the pedestal. Our air conditioners are also heat pumps and we have found them to be the most efficient way to heat the unit as long as outside temps are above 40°. If below 40°, we use the furnace(s) which use very little electricity. Electric heaters are about the most inefficient way you can heat a coach.

[fj12ryder]

2oldman wrote:
I don't know, but why don't you use the furnace?

Probably because electricity to run the heaters is included in the cost of the site, but propane costs extra. That's why I do it.

If you exceed the 30 amps, then the circuit breaker on the pedestal should trip.

[Sam_Spade]

Several things can happen.
IF....you have the adapter at or near to the supply pole, nothing bad should happen to the RV equipment.
BUT.....
The adapter might overheat.
The 30 amp receptacle might overheat.
The 30 amp breaker at the supply outlet might trip.

It is really NOT good to exceed a 25 amp draw on a 30 amp service because you don't know how good the feed really is.

[2oldman]

I don't know, but why don't you use the furnace?