30 amp plug into 50 amp socket

[jgmcbride]

I have a 2011 Winnebago Vista which is 30 amp unit. A fellow RVer once told me before I had this unit, that it is a good idea to carry an adapter so that if only a 50 amp RV site was available I can still plug in.

Tonight I purchased one. For the life of me, I can't think of any drawbacks in using it if I were to need to plug into a 50 amp source.

How about it, guys (girls)??

[KIX]

There is no drawback assuming the 50 amp receptacle is wired correctly. If you don't know how to check for correct wiring it would be a good thing to learn.

[TXiceman]

Your RV is protected for the 30 amps base don it's 30 amp breakers.

ken

[UFO Pilot]

After electrical problems with 2 different RV's, I wouldn't plug into any circuit without using a surge protector. My SurgeGuard will not let "bad current" to pass thru it and will protect in case of a circuit goes "bad" after I have plugged the RV in. Others opinions may be different.

[Bug512]

Personally I would not do it.

A circuit breaker always protects the wire downstream. So sure the breakers in the camper will protect the wiring in the camper..
But what protects the cord that goes from the receptacle at the campground to the electrical distribution panel in your RV ? Answer is the breaker on the pole where you plug into.
So if you have a 30 amp cord and plug into a 50 amp outlet. Let's say something happens to the cord or the panel in the RV. The breaker will never trip. The cord or panel (on the line side) will start to get very hot, melt or catch fire.

Remember the breaker always protects what is down stream. In this case the cord and panel .

[ernieh]

"But what protects the cord that goes from the receptacle at the campground to the electrical distribution panel in your RV ? Answer is the breaker on the pole where you plug into."

It doesn't matter. If the cord has a short (the only fault that would not trip the breaker on the coach) it needs to be replaced anyway.

[Bug512]

If the cord has a short it will overheat and the breaker will never trip until its melted or on fire.

[Workshop]

Quote:

Originally Posted by jgmcbride I have a 2011 Winnebago Vista which is 30 amp unit. A fellow RVer once told me before I had this unit, that it is a good idea to carry an adapter so that if only a 50 amp RV site was available I can still plug in. Tonight I purchased one. For the life of me, I can't think of any drawbacks in using it if I were to need to plug into a 50 amp source. How about it, guys (girls)??

...back to the question....there isn't anything wrong in carrying an adapter that allows you to use a 50a pedestal if that is what's assigned or available. That would be like asking if I should carry a 30a adapter because my unit has a 50a cord and system.

As an example: a friend went to Bike Week earlier this year and his reservation had him on a site that had a 50a/15a only pedestal....being in a van camper and arriving at 9pm he was trying to decide how to connect. He called the office and they had someone meet him and provided him, with a deposit, an adapter....considering it was a warm nite, he was glad to run his AC.

To go in the opposite direction....The last time we stayed at Fort Clinch SP, the ranger was dealing, over the phone, with a person that had borrowed a friends motorhome and had plans to spend the week enjoying the beach....only problem was he wasn't able to connect his 50a cord into a 30a pedestal. NO adapter, its Sunday afternoon and the closest RV dealer was near Jacksonville. Come to find out the guy was two sites down from me...as he seemed like an honest guy...I loaned him my 50/30 adapter so he was able to get connected and settled in. The next day he purchased one and returned mine.....

I don't see a down side to carrying adapters.

workhorse

[Route 66]

I see no problem either.

[vermilye]

Quote:

Originally Posted by Bug512 If the cord has a short it will overheat and the breaker will never trip until its melted or on fire.

If the cord shorts, enough current will flow to open the fuse or breaker long before the cord melts. A piece of #10 wire can carry 50 amps for a short time (long enough to trip a breaker) without a problem. An actual short will draw far more than 50 amps, tripping the 50 amp breaker quick enough to protect the wire.

As other have stated, the 30 amp breaker in your RV will protect against small overloads that, if continued over a long time, could damage the cord & connector.

[Midniteoyl]

Just bought 2.. a 30 to 15, and a 30 to 50.. both purchased at Smith Farms (ACE Hardware) for $3.99 and $4.99 respectively. Cheap way to ensure you have power.. Do you need to watch that you dont overpull on the 30amp cord? Of course.. but dont you do that anyways?

[Bug512]

Quote:

Originally Posted by vermilye If the cord shorts, enough current will flow to open the fuse or breaker long before the cord melts. A piece of #10 wire can carry 50 amps for a short time (long enough to trip a breaker) without a problem. An actual short will draw far more than 50 amps, tripping the 50 amp breaker quick enough to protect the wire. As other have stated, the 30 amp breaker in your RV will protect against small overloads that, if continued over a long time, could damage the cord & connector.

No the 30 amp breaker in your RV will not trip in your RV if the cord is shorted...

A breaker will only protects what is down stream....

Please message me if you have a problem understanding this. I would be happy to talk to you on the phone and discuss this ..

[RustyJC]

But the 50 amp breaker in the shore power pedestal will.

Rusty

[Dr4Film]

I am not an electrical engineer and I know enough about this stuff to be very dangerous so this is my take on it and it may not be completely correct but I think it is close.

First of all, the 50amp to 30amp adapter will not draw 50 amps. Remember that a 50amp coach with a 50amp shore power cord is only pulling a total of 50 amps over 2 completely different 120 volt legs. So a 50amp to 30amp adapter is built to only use one leg of the 50amp circuit which will be 120 volts, most likely 20-25 amps at the most, you will not get a full 30 amps I believe. Similarly, when someone that has a 50amp shore power cord and uses a 30 amp adapter to a 30 amp receptacle, they are now only using 30 amps distributed over both legs such that you will only be able to run certain item's in the coach, otherwise you will trip the breaker, burn up the receptacle or adapter, or some other electrical damage. Most 50 amp coaches generally have some sort of EMS system to monitor the 30 amps usage such that it will start shutting down devices that you can not use because of too many amps being drawn already for other stuff.

Dr4Film ----- Richard.