Circut breaker question

[GHOST1750]

My granddaughter who lives in Las Vegas has a travel trailer with one A/C. she bought another A/C to plug in in the trailer but it tripped the circuit breaker on 30 amp. If she used an adapter and plugged into 50amp would that cause damage to the trailers electrical system.

[opnspaces]

With no available 120v outlet on the panel then yes she can get adapters to do what she needs.

1 50A to 30A adapter to plug the trailer into the 50A outlet.
Link to 50 to 30 amp adapter
Then a 30A to 20A adapter for an extension cord to the second AC.
Link to 30 to 20 amp adapter
and finally a 12g extension cord. the shorter the better.
Link to 12G outdoor cord

She plugs the trailer into the 50amp adapter at the post.
She plugs the extension cord into the 30amp adapter that is plugged into the 30amp outlet at the post.

[enblethen]

No, I have no main breaker, I have three breakers to turn off all power to rig in the breaker panel.

[ktmrfs]

enblethen wrote:
No main breaker is required. Main is required if it requires more then six operations to disconnect power.
My Pace Arrow does not have a main!

At one time that was NEC code for houses but what I remember was 5 operations max to disconnect power. Common setup was Range, Stove, Dryer, maybe one other 220 appliance then another 220 breaker feeding ALL the 120V circuits. 5 motions, turned off power.

Not sure that is still allowed by code.

None the less, If the Pace arrow has no main breaker it is definitely in the minority, the common WFCO panel as a 30 or 50A main breaker feeding the panel. And the WFCO is used in the vast majority of trailers built in the last 20 years, The others are similar with a main then the other breakers.

[Bobbo]

enblethen wrote:
Good chance that the rig has no main 30 amp breaker.

No main breaker means no breaker panel, which means no power cord.

enblethen wrote:
No main breaker is required. Main is required if it requires more then six operations to disconnect power.
My Pace Arrow does not have a main!

So, you are saying there is no way to turn off all 120v power in your Pace Arrow other than to go out to the power pedestal and flip its breaker? I find that hard to believe.

[enblethen]

No main breaker is required. Main is required if it requires more then six operations to disconnect power.
My Pace Arrow does not have a main!

[GHOST1750]

Thanks for all the input, Your information is the same as I gave my granddaughter. Just talked to her, problem is there is no 110 outlet on the post outside her trailer. Youall have a cool summer.

[KD4UPL]

enblethen wrote:
Good chance that the rig has no main 30 amp breaker.

Really? What RVs have you been looking at? Every RV I've ever owned, worked on, or looked at in the last 20 years has had a main breaker.

OP, there's nothing wrong with plugging a 30 amp RV into a 50 amp outlet using an adapter. Many people do it all the time. However, it won't help the situation at all. Any load above 30 amps will still trip the main RV breaker.

[cavie]

All RV have a main Breaker.

[ndrorder]

Best bet is power the second AC with an available extra outlet on the pedestal. If there isn't an additional 110 outlet, something like this can be plugged into an available 50 amp plug on the pedestal. Since 50 amps of power will be available consider extension cord with a 20 amp breaker will protect the expensive A/C.

https://smile.amazon.com/EPICORD-Adapter-TT-30P-Female-handle/dp/B07KYKWP6B/ref=sr_1_1_sspa?dchild=1&keywords=50+amp+rv+splitter&qid=1590775993&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExTUNJT0pHTVhKQ1Q4JmVuY3J5cHRlZElkPUEwNDY3NzI1REk0R1ozTlAxNTYwJmVuY3J5cHRlZEFkSWQ9QTA3MjQ0ODEzSFNJUDIzWkJaQzg0JndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

[enblethen]

Good chance that the rig has no main 30 amp breaker.

[Bobbo]

Like has been said, the 30 amp breaker inside the trailer will trip so it won't work. Like has been said, the only two solutions are to run an extension cord from the power pedestal to the second A/C, or to upgrade the trailer's power supply from 30 amp to 50 amp. Option two is neither cheap nor easy.

[Beverley_Ken]

"If she used an adapter and plugged into 50amp would that cause damage to the trailers electrical system."
No, the input breaker on the trailer system would be a 30 amp breaker and would trip if the trailer (2nd AC unit) plus other things tried to pull more than the 30 amps.

Ken

[enblethen]

She could run an extension cord from the power pedestal to the new AC unit. Needs a healthy 312 extension cord for best results.
Not a good idea to try to overload existing trailer electrical system.

[AppFire]

Would not be good for it. The TT is rated for 30 amp service. If you want 50 amp usage you would need to change out the 30amp box for a 50 amp box and do some rewiring. Her solution to avoid that is to plug in the new AC directly to the power stand outside on a seperate circuit. Most power poles have a 30 amp, 50 amp and also a 15 amp service there on the pole.