50 amp ems plugged into a 30 amp outlet

[tomkatb]

I just reserved a state park campsite with 30 amp service.

As my fifth wheel is 50 amps I have only a Progressive 50 amp ems.

Can I assume I can plug my 30amp / 50 amp dog bone into the pedestal then the ems then my cord.

The ems will work that way? The Progressive site had little info on this.

[Tucson Joe]

That is what I do at home. Only have 30 amp service. Works out OK.

[tomkatb]

Thanks!

I assumed it would be ok. There would be less amps.

[BuzzWolfAR]

I do that frequently. No issues.

[Scrapper]

Originally Posted by tomkatb

Thanks!

I assumed it would be ok. There would be less amps.

You are correct in your assumptions. Instead of 50A on each line of your service, you will have a total of 30A on both lines. You have to closely manage your amperage usage.


For more info on RV electricity see the following link. New to RV's helpful hints by wmtire

[Tom Sundown]

Originally Posted by Scrapper

You are correct in your assumptions. Instead of 50A on each line of your service, you will have a total of 30A on both lines. You have to closely manage your amperage usage.


For more info on RV electricity see the following link. New to RV's helpful hints by wmtire

I am hardly an electrical expert but I believe you may have 30 amps available on both lines but only a total available of 30 amps. Both lines cannot pull 30 amps at the same time. If a 10 amp load is on one line then there is only 20 available on the other line. I am sure someone more savvy than me will chime in and correct or support my comments.

[CedarCreekWoody]

You will have less power available, of course, but the EMS will still provide protection from low volts, etc.

[andymil]

Originally Posted by Tucson Joe

That is what I do at home. Only have 30 amp service. Works out OK.

X2.

[wmtire]

Originally Posted by Scrapper

You are correct in your assumptions. Instead of 50A on each line of your service, you will have a total of 30A on both lines. You have to closely manage your amperage usage.


For more info on RV electricity see the following link. New to RV's helpful hints by wmtire

Originally Posted by Tom Sundown

I am hardly an electrical expert but I believe you may have 30 amps available on both lines but only a total available of 30 amps. Both lines cannot pull 30 amps at the same time. If a 10 amp load is on one line then there is only 20 available on the other line. I am sure someone more savvy than me will chime in and correct or support my comments.

Tom, it is correct that there is only 30 amps total, shared amongst both the L1 and L2.

That is what scrapper and you are both saying when you look at what I emboldened in red for both of you.

[Johntgif]

Note that the dog bone adapter from the 30 amp pedestal to your RV 50 amp shore line will apply 115VAC to both L1 & L2 circuits with much less amperage available TOTAL.

On a true 50 amp hookup, each (if equipped with two) A/C units are on separate 50 amp legs of the circuit breaker. If using the adapter, do not try to use both A/C units simultaneously.

Happy camping

[lewisra]

So with that being settled, it raises another question. I currently have a 30 amp TT, considering the cost of an EMS, could I buy a 50amp EMS now and use safely with appropriate adapters? Just thinking I’d be covered if I get a 50amp RV in the future.

[youroo]

Originally Posted by lewisra

So with that being settled, it raises another question. I currently have a 30 amp TT, considering the cost of an EMS, could I buy a 50amp EMS now and use safely with appropriate adapters? Just thinking I’d be covered if I get a 50amp RV in the future.

Yes this has been covered many times! Simple "Jumper Wire" but this ONLY applies to a Hard Wired Unit,No Portable ones! Youroo!!

[CHICKDOE]

this is just me so take it as such. i see this question posted repeatedly. can i buy a 50 amp ems now and use it with my existing 30 trailer as i might upgrade to a 50 amp trailer later. i agree, yes it will work. but what are you really saving? you'll pay $100 more to get the 50 amp ems. and you will need a 30 amp to 50 amp adapter to connect the ems to the 30 amp outlet on the pedestal and then a 50 amp to 30 amp to connect the 30 amp shore power cord to the 50 amp output of the ems. you could plug the ems into the 50 amp pedestal outlet but then don't expect that circuit breaker to provide any protection. you will only have the 30 amp circuit breaker in the trailer. should there be an electrical issue prior to getting to the circuit breaker in the trailer you will not have any protection. i would feel better with 30 amp on the pedestal and 30 amp in the trailer.

now if you later upgrade to a 50 amp trailer it is going to cost you some money. yes you will need to purchase a 50 amp ems. spending $400 at that time for a 50 amp ems seems like a small amount compared to what you will be spending for the new trailer. if you finance the trailer have the dealer provide a new ems and add it to the amount financed. it will only increase the payments by a few dollars.

again just my thoughts.

[lewisra]

Originally Posted by CHICKDOE

this is just me so take it as such. i see this question posted repeatedly. can i buy a 50 amp ems now and use it with my existing 30 trailer as i might upgrade to a 50 amp trailer later. i agree, yes it will work. but what are you really saving? you'll pay $100 more to get the 50 amp ems. and you will need a 30 amp to 50 amp adapter to connect the ems to the 30 amp outlet on the pedestal and then a 50 amp to 30 amp to connect the 30 amp shore power cord to the 50 amp output of the ems. you could plug the ems into the 50 amp pedestal outlet but then don't expect that circuit breaker to provide any protection. you will only have the 30 amp circuit breaker in the trailer. should there be an electrical issue prior to getting to the circuit breaker in the trailer you will not have any protection. i would feel better with 30 amp on the pedestal and 30 amp in the trailer.

now if you later upgrade to a 50 amp trailer it is going to cost you some money. yes you will need to purchase a 50 amp ems. spending $400 at that time for a 50 amp ems seems like a small amount compared to what you will be spending for the new trailer. if you finance the trailer have the dealer provide a new ems and add it to the amount financed. it will only increase the payments by a few dollars.

again just my thoughts.

So If I plug the EMS into 50 amp pedestal, plug 50–>30 amp pigtail to my 30 amp shore power, the EMS won’t protect me? Just want to be clear.

[CHICKDOE]

it will protect you for what it was designed to do. over /under voltages and surges. they do not protect for amperage. even if they did the 50 amp ems would not take any action until either leg exceeded 50 amps. what i was trying to say was when you are plugged into a 30 amp circuit breaker on the pedestal, it will protect the shore power cable and connections into the trailer up to the main distribution box. these are rated for 30 amps. if something goes wrong with these while plugged into a 30 amp pedestal breaker the pedestal breaker will trip. inside your trailer the 30 amp breaker in the main distribution panel will protect from using more than 30 amps inside the trailer. if you plug into a 50 amp pedestal the 30 amp breaker within the trailer will still protect from using 30 amps within the trailer. but the path from the pedestal into the trailer to the main distribution box which is rated at 30 amps is now protected by a 50 amp circuit breaker on the pedestal. so conceivably you could overload this portion of the incoming circuit without the pedestal breaker tripping. this would be some form of loose connection or short prior to the main distribution panel. i agree this is probably a low probability occurrence, but what is the expected outcome should it occur?

[youroo]

If you use a "HARDWIRED 50" inside your 30 A Unit there is NO Need for ANY Adapters! Then when you move to a 50 A unit you simply remove the jumper and install the "Hardwired EMS" into the 50A unit! No need to buy/sell a 30A EMS at a LOSS then Buy a 50A EMS! They at one time had a "LIFETIME Warr" which even made it More Flavorful for the Original Owner since it was covered for "Lifetime"! Youroo!!

[lewisra]

Got it, thanks to both of you!

[Scrapper]

If you buy a 50A portable and plug it into a 50A pedestal you will need a 50A to 30A dogbone to plug your 30A power cable into. The only time you need a 30A to 50A dogbone is if you happen to get a site with a 30A pedestal only.


If you get a 50A hardwired EMS then you need to put a jumper from line 1 to line 2 so the current pickup for line 2 can detect power, otherwise the EMS will not energize.

[4garylee]

Here is the answer - https://www.homedepot.com/p/Camco-50...FQnEwAodzF4FNg

https://www.walmart.com/ip/Camco-RV-...apter/29764592

[CHICKDOE]

yes that adapter would possibly help. i have never used one so i have no personal experience. the one thing that would concern me about it is how it supplies power to the two 50 amp legs. it will put 15 amps on one leg and 30 amps on the other. now if you are lucky your air conditioner will be wired to the 30 amp leg. if so it will run. but if it is wired to the 15 amp leg, it probably won't run. if you use a 50 to 30 amp adapter to convert the 30 amp pedestal receptacle to both legs of the 50 cord you will be able to run the a/c as either leg has up to 30 amps on it. but you only have 30 amps total between both legs.