Electrical Adapter Question

[Double Eagle]

My RV is wired with a 30 amp powercord; I had a second A/C installed on the unit that is also wired for a 30 AMP powercord. In my expierence most pedistals only have one 30 AMP plug and one 50 AMP plug. My thoughts were to get a 50 AMP to 30 AMP adapter and plug the main RV powercord into this adapter and run the main RV powercord off the 50 AMP power outlet and run the second A/C off the 30 AMP plug at the pedistal. Will this cause any problems? Does anyone have a better suggestion? What about a surge protector; I have read you cannot plug a 30 AMP surge protector into the 50 AMP to 30 AMP adapter. I would assume I would need to buy a 50 AMP surge protector and then plug the adapter into it. Any thoughts or suggestions?

[Terry]

I dont think it matters on the surge protector...I dont think it generally matters if it is a 30 or 50 amp circuit.....

I guess I am a little confused? Do you have two 30 amp power cords coming from your unit or is that a mod you are making? If you are making mods, I dont see why it would not work if wired properly and has the proper breaks/protection in line.

[clutch]

As long as the second power cord is just for the AC I would use a 50 to 30 adapter for one and use the 30 for the other.

[Double Eagle]

Originally Posted by tafische

I dont think it matters on the surge protector...I dont think it generally matters if it is a 30 or 50 amp circuit.....

I guess I am a little confused? Do you have two 30 amp power cords coming from your unit or is that a mod you are making? If you are making mods, I dont see why it would not work if wired properly and has the proper breaks/protection in line.

Yes the dealer installed the second A/C and it does have it's on 30 AMP powercord and seperate breaker.

Thanks for info; that was my plan to run the main RV 30 AMP powercord on the 50 AMP supply using the adapter, but just wanted to make sure it would not cause problems with the electrical system. Just wanted to make sure I could also plud a 30 AMP surge protector into that 50 AMP adapter as well.

[FPM III]

Originally Posted by clutch

As long as the second power cord is just for the AC I would use a 50 to 30 adapter for one and use the 30 for the other.

If the above is true, you should be able to plug the line with just the A/C unit into the 20A using a 30A to 20A adapter. Then, you don't have to bother with the 50A circuit at all. That's how RVs requiring 50A service can get it when only a 30A and 20A recepticle are in the box. They use a special cable that has a 30A and 20A plug. The only danger they have when using it is that the polarities must be correct in both recepticles. This should not be a problem in the OP's case as his he appears to have two distinct circuits.

There are two additional advantages for using a 30A/(30A)20A setup as opposed to a 50A(30A)/30A.

1. A 30A/20A recepticle box is more commonly found in campgrounds
2. Campgrounds often charge extra for 50A service

[Double Eagle]

Originally Posted by FPM III

If the above is true, you should be able to plug the line with just the A/C unit into the 20A using a 30A to 20A adapter. Then, you don't have to bother with the 50A circuit at all. That's how RVs requiring 50A service can get it when only a 30A and 20A recepticle are in the box. They use a special cable that has a 30A and 20A plug. The only danger they have when using it is that the polarities must be correct in both recepticles. This should not be a problem in the OP's case as his he appears to have two distinct circuits.

There are two additional advantages for using a 30A/(30A)20A setup as opposed to a 50A(30A)/30A.

1. A 30A/20A recepticle box is more commonly found in campgrounds
2. Campgrounds often charge extra for 50A service

I thought of using a 30 to 20 adapter, but cannot find that adapter anywhere; All I can find is a 30 to 15 and the A/C installer said it is not good to run the A/C on a 15 AMP outlet because the A/C is usually pulling around 18 AMPS on start-up. The installer also told me they did not make a 30 to 20 adapter, not sure if this is true, but I have not been able to find one.

[29BHS ECO]

The post in the CG may have a 50A & A 30A outlets but thats not to say you can get 80A out of it. They probobably only have 50A available but provide both 50& 30A outlets so it will take what ever configuration the cord your RV/TT has. To get real technical your TT may never draw 50A ( by the electical code it's called deverisification)the code writers know that you won't run all your elect appliances and use all the outlets at one time so evan though you have a 50A cord and breaker you might never exceed 20-30a. If you add up all the wattages on your home appliances, convert that number to amps it could be as high as 600a and guess what your house service is maybe 100 or at the most 200a.

[Double Eagle]

Does anyone know if it is safe to plug a 50 AMP to 30 Amp adapter into the 50 AMP plug on pedistal and them plug a 30 AMP surge protector into that adapter. I read somewhere on the internet that this would increase the volts to the surge protector causing it to trip due to the surge in power from the 50 AMP since the surge protector is only rated for 30 AMP. Is this true or can this be done with a 30 AMP surge protector?

[Terry]

Let me ask you this --- I thought that most 2 AC campers had a 50 amp plug? Since it is really two 50 amp 120 volt circuits - I thought they put most of the camper and an AC on one leg and the second AC on the other leg. Wouldn't that make more sense that having two 30 amp cords? If you had a 30 amp only site, you would be limited to one AC unit. You could also use the "cheater" that allows you to hook to a 30 and a 20 amp outlet and power both legs. Couple that with a good EMS and I would think it would be a nice setup.

[Terry]

Originally Posted by Double Eagle

Does anyone know if it is safe to plug a 50 AMP to 30 Amp adapter into the 50 AMP plug on pedistal and them plug a 30 AMP surge protector into that adapter. I read somewhere on the internet that this would increase the volts to the surge protector causing it to trip due to the surge in power from the 50 AMP since the surge protector is only rated for 30 AMP. Is this true or can this be done with a 30 AMP surge protector?

Sure - you can do that. A surge protector protects in high spikes in voltage, regardless of the amperage. As long as your TT is 30 amps and your surge protector is rated at 30 amps you are good to go. The surge protector will have no idea it is really plugged into a 50 amp.

[Double Eagle]

Originally Posted by tafische

Let me ask you this --- I thought that most 2 AC campers had a 50 amp plug? Since it is really two 50 amp 120 volt circuits - I thought they put most of the camper and an AC on one leg and the second AC on the other leg. Wouldn't that make more sense that having two 30 amp cords? If you had a 30 amp only site, you would be limited to one AC unit. You could also use the "cheater" that allows you to hook to a 30 and a 20 amp outlet and power both legs. Couple that with a good EMS and I would think it would be a nice setup.

Most of the Eagle Super Lites come from the factory with only 30 AMP service; the 31.5 FBHS only comes from the factory with 30 AMP service and a second A/C cannot be added at the factory for this reason. 30 AMPS would not be enough service to run both at the same time, so I had to have the RV dealer install the second and run it on its own powercord and breaker. The adapter you are showing is a 30 AMP and 15 AMP that allows you to plug a 50 AMP cord into the adapter and get 45 AMPS. both my cords are 30 AMP plugs so this adapter would not work; however I have seen a 50AMP adapter that has to 30 AMP pigtails that could work (not sure). I am not an electrician so not sure the best way to plug the rv in. My thoughts would be again to run the RV 30 AMP powercord to the 50 AMP plug using an adapter and surge protector ad thei run the second A/C powercord to the 30 amp plug. Just wasn't sure if this would harm electronics over time.

[TexasA&M]

What happens when you go to a campground that only has 30amp service though?

Also, I thought that most campgrounds had either 50 or 30, but not both at the same site. Are there a bunch out there that have both available?

[Terry]

The adapter you are showing is a 30 AMP and 15 AMP that allows you to plug a 50 AMP cord into the adapter and get 45 AMPS

Right - I was suggesting that it might be better to convert the camper over to a 50 amp plug and it might make your life much easier in the long run - but I realize that is quite a bit more work.

The potential problem I see is that you could end up pulling both plugs from the same leg. You run the risk of overloading one leg if the pedestal can not support that much current.

This may be a better solution given your wiring situation:


This should pull 30 amps from each leg and you dont run the risk of overloading anything. Only downside is you can only run one AC unit if you are at a 30 amp only site - but I think you would have that limitation anyway.

[Terry]

Originally Posted by TexasA&M

What happens when you go to a campground that only has 30amp service though?

Also, I thought that most campgrounds had either 50 or 30, but not both at the same site. Are there a bunch out there that have both available?

Every 50 amp site I have been to also had a 30 amp plug and a standard duplex outlet.

[Double Eagle]

Originally Posted by tafische

Right - I was suggesting that it might be better to convert the camper over to a 50 amp plug and it might make your life much easier in the long run - but I realize that is quite a bit more work.

The potential problem I see is that you could end up pulling both plugs from the same leg. You run the risk of overloading one leg if the pedestal can not support that much current.

This may be a better solution given your wiring situation:


This should pull 30 amps from each leg and you dont run the risk of overloading anything. Only downside is you can only run one AC unit if you are at a 30 amp only site - but I think you would have that limitation anyway.

Yea, as long as the RV park has a 50 and a 30 i would be okay, but you are right if only one 30 plug I would not be able to run the second A/C. The adapter you are showing now is the one I was talking about but was not sure if it would put 30 amps to each cord.

[Terry]

It should give 30 to each size, but obviously you want to verify that is how it is made. A 50 amp circuit is actually two 120 volt legs, each with 50 amps - so it is a lot of power and cover what you have with no problem.

[Double Eagle]

okay, thanks for the help

[clutch]

You probably won't need both air conditioners at the same time. One AC seems to be enough up to 100*.