Generator Circuit Breakers

[DSurette]

I went to the storage lot to exercise the generator and RV engine today. I noticed that the generator, an Onan QG5500, has two 30A breakers on the output. Checked on line and it seems that these are the correct ones. So how can a 50A generator put out 50 Amps with 30A breakers on the output?

[ependydad]

It's only about 46 or 48 usable amps. I forget which from when I read the documentation.

Each breaker feeds on leg of your 50amp service. You could potentially have 20 amps on one leg and 15 amps on the other and be running the generator at close to its maximum power.

[formerFR]

because it's not a 50amp generator

it is a 5500w generator, with two breakers(in a double pole configuration) to provide about 25amps @ 120v to each side of your '50amp' Main breaker box

you'll have 'less' power when you are on the generator than when you are plugged into full 50amp RV Shore Power

50amp Shore Power is actually 240v service, with 50amps to each side's Hot Leg, and into your coach, for a total of up to 100amps usuable. Your coach's breaker box split's these into two sides of service. It's doubtful you and me and most any other RV owner ever actually has any use for the 240v service, as it would require a double-pole breaker for such appliances as a 240v Dryer.

[bubbles]

Additionally, the generator is a single phase generator. It's similar but different to using a 30m to 50f adapter in its connectivity.

[DSurette]

Thanks for all the replies. I had been thinking that generator power was the same as plugging into the pole. Learning is a never ending process.

Thanks again.

[formerFR]

your generator simply 'generates' it's own 120v power, to use just as you use any Shore Power, or household outlet, even.... they are all the 'same' power to your coach.

What's different is:

- how many 'AMPS' you have to use - a typical 50amp RV Shore Power outlet give you two sides, both with 50amps, for a total of 100amps. A 30amp outlet only gives you 30. A household outlet only gives you 15 or 20. Your generator is giving you close to 50amps, between two sides to your Main panel, for a total of 50 only.

- most RV Generators, whether the onboard type, or one's you set outside, are only 120v power output, which is what you and I typically use anyway. But, some are 240v models, for larger motorhomes which have 240v appliances like a DRYER. This is really just like the typical 50amp RV Shore Power you and I normally plug into with our 50amp Shore Cord, but our Main panel inside our coach doesn't make use of the 240v, only two 120v sides.

long story, but true.