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2chiefsRus's avatar
2chiefsRus
Explorer
Jul 13, 2019

Campground Breakers - EDITED

We have been traveling in our current motorhome for nearly 12 years, with 8 years of it as full timers and the last four at 3/4's of the year so we are very familiar with this coach. I heard something yesterday from a campground owner that I doubt. The campground's electrician said that the campground breakers on the pedestal do not get weak over time and should not need to be replaced.
Here's the situation - pulled in to the campground, plugged into 50 amp, Progressive Industries hardwired unit showed good power, fired up both air conditioners and after about 1 hour, the campground breaker tripped. PI showed no errors.
We shut down both AC's, reset the pedestal breaker, and started up one AC only for about 2 hours. By that time it was cool enough that we didn't need AC for the night.
Two days later, we fired up one AC and then the second AC about 15 minutes later, and the pedestal breaker tripped again after 45 minutes of both AC's running. Reported problem to Campground, said they would look into it.
Next day, exactly same situation when we turned on both AC's, one first and then the second one 15 minutes later. From what I have read on this forum, it sounded like a weak breaker that needed to be replaced. That is when we were told that breakers don't get weak and need to be replaced.
What do you think? Could this be a problem with something going wrong in our coach as the campground is implying? We will be moving campgrounds in a couple days and want to know what to be watching.

EDITED TO ADD - Moved to another campground and both AC's ran for over 4 hours without any problem at all. So I guess the electrician at the last campground has some work to do.

46 Replies

  • accsys wrote:
    Since you have a Progressive Industries unit, I would keep an eye on how much current both lines are drawing so you could tell management, or the electrician, how much current was being pulled when the breaker tripped.

    Good idea, the PI monitor is outside so watching it is not very convenient. I should also mention that we have unplugged from the 50 amp outlet and used a dogbone to plug into the 30 amp outlet. We no longer have pets, so we have no need to leave the AC's running during the day while we are out. Our primary concern is making sure we don't lose power to the refrigerator or run our batteries down.
  • Any way to run the power cord to an adjacent power pole?
    If the campground voltage is low due to load the current draw of your devices would go up possibly beyond the capacity of the breakers. So it may be doing its job by tripping due to overload. I'm remembering my semester of electrical engineering that Power = volts x amps. The power is what the a/c requires and the volts is the campground level (normally 120 +/- 10%.
    I'm no electrician but I have replaced c/b in home panels when the breakers went bad.
    The c/g electrician should have one but a clamp on ammeter is available from many sources for less than $20. It would measure the a/c current but you have to separate the conductors since one cannot clamp on the entire power cord.
  • Flute Man wrote:
    Circuit breakers are thermal devices and trip when they get hot. I think the pedestal should be examined for loose or poor connections. Poor connections will also generate heat and cause the breaker to trip.
    Jerry Parr

    Thank you for your reply - the campground did have someone, not the electrician, come by who opened up the pedestal and looked for loose wires and signs of burning or singeing. Didn't see anything obvious.
  • Since you have a Progressive Industries unit, I would keep an eye on how much current both lines are drawing so you could tell management, or the electrician, how much current was being pulled when the breaker tripped.
  • What was the current draw on each of the two legs with both air conditioners running? Without knowing that, it's impossible to say with any real certainty if the breaker was working properly or not.

    Standard breakers operate thermally (for the most part--for very high current overloads, such as a dead short, they have a magnetic trip mechanism that acts more quickly). The average current being consumed is measured by how much it heats up a little bimetalic strip, and if it heats up and bends enough it causes the breaker to trip. Anything that makes it heat up more will cause the breaker to trip earlier--higher temperatures in the box than expected, poor contact between the breaker and the bus bars it's mounted on, or I presume poor contact internally in its contacts due to repeated tripping/disconnecting under load.

    My guess is that the breaker is in need of replacement, but without actual measurements of stuff it's nothing more than a guess.
  • Circuit breakers are thermal devices and trip when they get hot. I think the pedestal should be examined for loose or poor connections. Poor connections will also generate heat and cause the breaker to trip.
    Jerry Parr