Using 30A power in an RV wired for 50A

[TheBuckners]

We're new to RVs (other than pop-up campers when we were kids) and have a new Reflection 337RLS that is wired for 50A power and has two AC units (one 13.5k and another 15k). If we end up at a campground that only has 30A power (or only sites available with 30A), how does this work? We bought a 50A to 30A adapter, so we'll start by plugging that in at the pole, then using our 50A cord as usual. Does this mean that we'll only have about a 3rd of the power but can use any device we want? Or does this mean that only devices on one of the two legs can be used? My understanding is that on 50A, there are two legs and the appliances/outlets/ACs are separated between the two. It it's the latter, how do we know which items can be used when on 30A?

We also just bought a Champion 3100W generator that has a 30A outlet, so can I assume that it'll be just like plugging into a shore 30A outlet? Or different...

Thanks,

Alan

[theclarks]

With 30 amp service you'll be able run everything except "both" AC's at the same time, either one but not both. We have the 303 with only the 1 AC, so I left the 50a cord at home and carry a 25' and 50' 30a cords. . . .

[Hickey]

Plugged in on a 30 amp rv post you should be able to run most things in your trailer, but not both AC units at the same time. You need the extra amps to run both.

On your generator, you should be able to run one AC just barely, but almost nothing else at the same time. Switch your fridge to propane if you need to do that.

I have the same trailer except just one AC unit on mine. I also have a similar rated generator, but I may need to buy a second one to keep it running while I run multiple appliances.

[carnolddsm]

Except for being able to run multiple air conditioners, 30 amp service is not a problem, don't worry about it.

If you find 30 amp service to be inadequate switch the refrigerator and water heater to propane.

With regards to running multiple air conditioners on 30 amp service, you may find this to be possible especially after the sun goes down. Outside temperature has a significant impact upon current draw (amps), for each 5 - 10 degree drop in outside temperature air current draw drops by one amp.

[TheBuckners]

Thanks everyone! Great to know that 30A will work for us :-)

I did some further research on the Champion Parallel Kit. Found this in the Q&A:

Q: Hello, I am considering purchasing two 3400 inverter gens and the parallel kit for my 50 amp service fifthwheel camper. Will both hot legs have 120v 25 ampish power supplied to the camper with this kit? Will I be able to run both 15k and 13.5 btu a.c. Units if they are on separate busses with this parallel kit? Or is only one leg powered with 50 amp 120v power and the other leg will be not powered? Thanks

A: It is 120V at 50A on a single leg. the other leg will not be powered at all. The camper will detect it is operating at 120 and respond accordingly, unless you have completely separate circuits. Thank you.

So based on only supplying a single leg, any idea what (if anything) I may lose using a parallel kit with two 28ish Amp units ganged together?

Thanks once again,

Alan

[arhayes]

Thanks everyone! Great to know that 30A will work for us :-)

I did some further research on the Champion Parallel Kit. Found this in the Q&A:

Q: Hello, I am considering purchasing two 3400 inverter gens and the parallel kit for my 50 amp service fifthwheel camper. Will both hot legs have 120v 25 ampish power supplied to the camper with this kit? Will I be able to run both 15k and 13.5 btu a.c. Units if they are on separate busses with this parallel kit? Or is only one leg powered with 50 amp 120v power and the other leg will be not powered? Thanks

A: It is 120V at 50A on a single leg. the other leg will not be powered at all. The camper will detect it is operating at 120 and respond accordingly, unless you have completely separate circuits. Thank you.

So based on only supplying a single leg, any idea what (if anything) I may lose using a parallel kit with two 28ish Amp units ganged together?

Thanks once again,

Alan

Your rig is wired where the AC's are on separate legs, so it seems this would still only allow you to run one AC.


Alan

[Cate&Rob]

Thanks everyone! Great to know that 30A will work for us :-)

I did some further research on the Champion Parallel Kit. Found this in the Q&A:

Q: Hello, I am considering purchasing two 3400 inverter gens and the parallel kit for my 50 amp service fifthwheel camper. Will both hot legs have 120v 25 ampish power supplied to the camper with this kit? Will I be able to run both 15k and 13.5 btu a.c. Units if they are on separate busses with this parallel kit? Or is only one leg powered with 50 amp 120v power and the other leg will be not powered? Thanks

A: It is 120V at 50A on a single leg. the other leg will not be powered at all. The camper will detect it is operating at 120 and respond accordingly, unless you have completely separate circuits. Thank you.

So based on only supplying a single leg, any idea what (if anything) I may lose using a parallel kit with two 28ish Amp units ganged together?

Thanks once again,

Alan

Alan - The 30A male to 50A female adapter provides the available 30A @ 120V to both legs of the 50A supply to the trailer. If your parallel generators are putting out 50A @120V you should be OK to run both AC units . . . as long as you don't use a 30A cord. The 50A cord could safely carry the entire output of the generator on one leg if the draw was this way. The only "at risk" part of this is the 30A male to 50A female adapter which might be rated for only 30A.

Rob

[D2Reid]

Three things to consider:

1. When on 30 amp service turn your water heater to the propane mode, that takes a pretty big load off of the electrical side. Some folks put the refrigerator in gas mode also, but I am not sure that takes much load off.

2. A quick and not very accurate way to check if you are drawing too much power is to put your hands on the different connections. If it feels very warm or hot you are drawing too much. Weigh in whether they are warm from the sun.

3. You may run up against a post that has a 30amp GFI breaker on it. I have had my 50 amp cable trip the GFI. I have never figured out why, but I carry an additional 30 amp cord that doesn't trip GFI's.

You may want to consider a Surge Guard protector, the one with the LED display that shows the amount of draw.

[TheBuckners]

Great input and advice everyone. Thanks!

[Steven@147]

Recently we were camping at a State Park where the 50 amp plug would not work so we ran on 30 amp for the long weekend. We have two AC units but only needed one to keep the coach cool so that wasn't a problem. You can only run one AC unit on 30 amp.
You just have to limit your usage while on 30 amp. In the back of your owners manual there is a chart of average amp usage for various appliances, this can help you calculate what you can use at the same time. For a specific appliance if you want to know how much power it draws, look at it, it will usually tell you how many amps it needs or will tell you watts, if watts divide by 120 to get @ amps. It also tells you how many amps the converter needs and so forth. Just add up the total amps of things turned on at the same time and keep it 30 or under.

Also we were able to turn things on and off at different times so not to overload the 30 amps circuit. For example since one AC unit in 95+ degree weather was keeping the coach cool, we would turn off the AC unit and turn on the electric water heater for a few minutes. Once the water got hot in the tank it would stay hot for a long time (hours) so we didn't need that on all the time. Then switch the electric water heater off and turn the AC back on. For 15-20 minutes with the AC off it didn't hurt a thing and we keep an electric floor fan running to circulate the cool air around the coach so the AC doesn't run a lot anyway. We could have run the water heater on propane but didn't need to. Also we could run the bedroom AC unit during the day to keep the noise up front and at night use the central AC unit to keep the noise away from the bedroom, just didn't use them at the same time.

We ran the fridge on electric all the time. We usually use electric cooking appliances but for this weekend we used more propane to cook. I like my own drip coffee and the wife likes her Keurig stuff. We just didn't have them on at the same time. Once my coffee was done I would switch it off and my coffee stayed hot in the pot for a long time, then the wife would turn hers on, it wasn't that big of the thing.

You know we have had or RV for over a year and use it pretty regular and we are still running on the first propane tank and haven't used all of it in that year to switch over to the second tank. We have even run the furnace a few times last winter when camping and still we haven't used up the first propane tank.

You know once you get used to limiting your power usage in your RV, you'll realize just how much power you waste at home.