Staying at a friends ranch and they are running a electric cable to a 50AMP outlet for our coach... but back at the breaker box it is coming off a dedicated 70AMP breaker.
Is this safe to power the coach?
Chris,
The rating on a breaker is the maximum number of amps it will pass before it trips. So a 70 amp breaker will allow a maximum of 70 amps to pass, and will not have an issue if your current draw is less than that.
Your coach has a 50 amp double pole breaker for its "main". If you look at the breaker box you'll see that breaker - by double pole, it looks like 2 breakers with a bar connecting them together.
50 amp for an RV is actually 2 power legs each of 50 amps, out of phase. That's why you see the double pole breaker for the main in the coach.
The electrician wiring the RV outlet should be using a double pole breaker for the service breaker as well.
Here's a pretty good website with info
http://www.myrv.us/electric/ (http://www.myrv.us/electric/)
I don't know why they would use a 70 amp breaker for the dedicated line, unless it's all they had. There's no reason to oversize the breaker on a dedicated circuit.
The only, "out there" concern I* can think of if all is wired correctly is that if for some reason there was a problem between your coach main and the service breaker that caused a greater than 50 amp draw on either (or both) legs, the service breaker wouldn't trip until there were 70 amps of current flowing. If the circuit wiring isn't sized to handle that maximum current (adequate gauge) there could be damage to the circuit wiring (which could include your coach power cord). Now, what happen in that situation would depend on why excessive current draw was happening.
*Keep in mind I am not a licensed electrician.
Do make sure the circuit is wired correctly with the proper gauge wire.
Michelle
Great help thanks all... I had the drawings for a correct 50 AMP and 30 AMP circuit so we checked the outlet before use and it is correct.
I was just a bit nervous about that 70AMP breaker, kind of figured the MH breaker could save the day in a bad situtation but I'm not the brightest bulb.... anyway as it turns out we found a 50AMP breaker in the tool shed and swapped it out. Up and running fine so no bonfire tonight