Forum Discussion
myredracer
Jul 29, 2019Explorer II
The difference between a 30 amp and 50 amp RV is a constant source of confusion on forums. A 30 amp RV is 120 volts only. A 50 amp RV is 120/240 volts EXACTLY a residential 100 or 200 amp panel. A 120/240 amp service does not have phases, it has 120 volts 1/2 way between the two 240 volt hot legs.
One thing about adapters and extension cords is that they aren't required to be UL listed. There's a lot of them on store shelves that aren't, including places like CW. I'd never buy one that isn't UL or CSA listed as you have no idea what it's like inside.
There is no issue using a 50 to 30 amp or 30 amp to 50 amp adapter. If you are 30 amps and have 50 amps available in a pedestal, it can sometimes be a good idea to use an adapter since 30 amp receptacles in pedestals can be in bad condition and result in overheating.
Having a breaker being able to operate for a short period over it's rating is advantageous sometimes and desirable. For ex., you can run a MW or hair dryer and be over 30 amps for a short period and not trip the breaker.

One thing about adapters and extension cords is that they aren't required to be UL listed. There's a lot of them on store shelves that aren't, including places like CW. I'd never buy one that isn't UL or CSA listed as you have no idea what it's like inside.
Sandia Man wrote:No. As mentioned, a breaker does not trip the instant it reaches it's rating. It's NOT how standard molded case breakers work. A breaker has an inverse time-current characteristic as shown in the standard graph below. They have a thermal magnetic element in them. As the element heats up, it trips sooner at higher currents. At short circuit levels, the magnetic element trips it instantaneously.
Head on over to your local wallyworld, they have a variety of adapters to handle any scenario. No circuit breaker required on adapters as your RV has a main breaker that will instantly open upon reaching its rated value. We use our 50 amp adapter often for our 30 amp rig since many power pedestals at older parks have very worn 30 amp receptacles.
There is no issue using a 50 to 30 amp or 30 amp to 50 amp adapter. If you are 30 amps and have 50 amps available in a pedestal, it can sometimes be a good idea to use an adapter since 30 amp receptacles in pedestals can be in bad condition and result in overheating.
Having a breaker being able to operate for a short period over it's rating is advantageous sometimes and desirable. For ex., you can run a MW or hair dryer and be over 30 amps for a short period and not trip the breaker.
About Technical Issues
Having RV issues? Connect with others who have been in your shoes.24,210 PostsLatest Activity: Mar 02, 2025