30 amp voltage

The 50A circuit CAN provide 250V, and there are a VERY FEW big 50A rigs that use it.

But that is NOT THE NORM! For nearly all 50A coaches, that system is TWO 125V/50A circuits. Your coach uses ONE 125V/30A circuit. That "A-Dapter" (I can't help quoting Johnny Cash) uses ONE of those 50A/125V circuits for you to plug your 125/30 into. The other 125/50 "Leg" is unused.

And YES it is safe to do this. 50A will not over-pump your electrical system since your coach's on board power panel's main breaker is 30A.

What's NOT safe is applying 250V to a 125V system, and the posts above have covered that.

JANETRUPP wrote:
Thanks all. I needed to know since the person replacing the 50 amp to a 30 amp wasn't sure if I needed the 30 amp that was 125 or 250 volt and the motorhome is not at the house yet, We are still on the road to get her.
Thanks again, I really appreciate all the help. This forum has always been a great help to me.
Janet

I'd be a little nervous using an electrician who didn't know that 30amp RV's are 120v.

It's possible he's competent and just never seen an RV but it doesn't leave me feeling comfortable if he's asking such a basic question.

As others have said, leave the 50amp outlet and use an adapter. It will save you money and leave you with a more capable outlet.

Thanks all. I needed to know since the person replacing the 50 amp to a 30 amp wasn't sure if I needed the 30 amp that was 125 or 250 volt and the motorhome is not at the house yet, We are still on the road to get her.
Thanks again, I really appreciate all the help. This forum has always been a great help to me.
Janet

JimmyRV wrote:
Use the adapter. If you ever sell the house, an rv savy buyer would take a 50 amp over a 30 any day. Keep the 50!

This is also what I would do. Cheaper and less hassle.

Use the adapter. If you ever sell the house, an rv savy buyer would take a 50 amp over a 30 any day. Keep the 50!

ALL good/correct answers!

You also could have the electrician wire the 30 Amp as above parallel, next to the 50 Amp and have both in case you go back to 50 Amp.

LEN

If you don't want to rewire the outlet, an adapter would work fine. First confirm that it is indeed providing ground, neutral, L1 and L2 conductors. With a meter test 120 Volts from neutral and ground to L1 and L2. Then confirm that there is 220 present between L1 and L2. If not, then the 50 Amp outlet is single phase. Keep in mind that the 220v 50 Amp to 120 Volt 30 Amp adapter only taps into the L1 phase and the overcurrent protection is still 50 Amps. If this is going to be a long term setup, I would rewire it in this fashion: Replace the 50 Amp outlet with a 30 Amp RV type. Spare the L2 conductor at both ends. Remove the 50 Amp dual breaker and replace with a 30 Amp circuit breaker in either of the now vacant positions. The remaining position now can be used for another dedicated circuit. An adapter is quick and dirty, but long term an outlet wired to code is the best.

This is what you should have for the RV 30A Shore Power Cable to plug into...


NO SHOCK ZONE image

This will be wired just like the 120VAC 15A-20A Receptacles but will be fed with a 30A Circuit Breaker...

You MUST tell the Electrician this is being wired for a RV Trailer setup and not a 240VAC Circuit for a 240VAC Home Dryer appliance...

NOTE these two 3-socket receptacles that look very similar. The one on the LEFT is for the 120VAC RV setup and the one on the RIGHT is for the 240VAC Dryer setup.

NO SHOCK ZONE Image

Forcing your RV Shore power cable into the receptacle on the right will destroy many 120VAC Appliances and system in your RV in a instance. This is a very good reason to use a licensed Electrician that has Insurance to cover these loses... you are talking about a few thousand dollars going up in BLUE SMOKE at the snap of a finger...

I am only passing this on for your education of the difference between the two very similar receptacles for two different system. I am NO EXPERT in any of this. Consult the Licensed Electrical Experts if you have questions...

Roy Ken

In the RV world there is only one connector for 30 amp RVs: NEMA 30TT at 125 volts.




http://www.myrv.us/electric/


250v is for some other appliance such as clothes dryer or welder.