30 amp circuit breaker

[geeman]

I'm a new 2011 Flying Cloud owner. My power went off and I determined that the 30 apm breaker switch went off and won't stay back on. It is part of a 20/30 amp switch. We had the heat pump on and a few plug ins on and we turned on the microwave. That is when it went off. Does anyone know how I get the breaker out. Or should I call a repair guy? Should this have happened on a relatively knew FC? Thanks for any help.

[newroswell]

geeman, are you saying the breaker won't stay back on after turning something off? The 30 amp is going to be the main breaker and it appears you have exceeded 30 amps total, even though you haven't exceeded any individual 20 amp load.

Sometimes when the breaker switches off, you need to push it all the way off before resetting it also.

[dkottum]

The heat pump draws a lot of power, and can get "iced up" when the weather is cold. This would put a sudden load on it, that with everything else overheated the breaker and turned it off. The breaker would need to cool before resetting.

If that's not it, it may be too much load overall. An easy way to add up the load is to look at the wattage on your plugins, divide by 100 to get ballpark amp load. That is added to all other electrical equipment in the trailer.

Check the easy stuff first.

doug k

[345bill]

Same happens in our motorhome when microwave is added to circuit that already has other items in use. You'll learn to turn off some loads before using microwave.

Agree with Chief Chili Cook about turning breaker all the way off, let it sit a minute then try to re-set it.

[aftermath]

First of all, when you say that it "won't stay back on." Do you mean that you reset the breaker and it tripped again or it never reset in the first place?

If it hasn't reset, try turning it completely off and then back on. You might have to replace the breaker but that shouldn't be a big job. I do not have access to my trailer right now so I can't give you any definitive suggestions on the replacement but I think they are very similar to a house breaker.

You might want to check up the line and see if the circuit you are plugged into is still functioning. Are you home? Perhaps the main 30 amp breaker in the house has tripped.

If the trailer breaker does reset and then immediately trips again you might have a short somewhere or you still have the heat pump and microwave turned on. Unplug the microwave and see if that helps.

Good luck with the mystery. There is always a mystery......

[ventport]

Turn everything off before you try to reset the breaker. Then turn stuff on one at a time. If it trips on the first item, it may be the item is shorted. If it trips with a lot of stuff on, you probably exceeded 30 amps.

[afneill]

When you are calculating the load on your circuit, know that a circuit breaker is designed to trip at 80 per cent of its nameplate rating, in this case that would be 24 amps. If the circuit is pulling 25 amps the heat build up will cause it to trip. That is the way they are designed.

[geeman]

Thanks to all of you. Your collective advice worked. I pushed down firmly on the breaker switch and then pulled it up (on). It worked!

[markdoane]

Originally Posted by afneill

When you are calculating the load on your circuit, know that a circuit breaker is designed to trip at 80 per cent of its nameplate rating, in this case that would be 24 amps. If the circuit is pulling 25 amps the heat build up will cause it to trip. That is the way they are designed.

I didn't know that.

[afneill]

Most circuit breakers made today and certainly those used for residential application, such as those in the Airstreams today, are a combination electromagnetic/thermal breaker. If a short circuit occurs the elctromagnetic application will cause it to trip almost immediately. With an overloaded circuit the thermal properties will cause it to trip, the length of time to trip being determined by the level of overload or heat build up. And many people do not realize the breaker is sized to protect the wire and its insulation, not the device on the circuit, although it may be protected in the process. Sorry. Did not mean to hijack the thread.

[CalamonTin]

I have also had some times, in the hottest part of the summer, when my 30 amp breaker trips. Repair guy explains my overload with the AC on, the TV on and the water heater cycles and the breaker trips. I let it cool and reset it, ran a test turning things back on and it repeated the trip. Repair guy says to consider upgrading to 50 amp service or put in another 30 amp box, take the water heater or AC on the new box thereby reducing the load on either. Says install second 30 plug adjacent to the exiting one. Says I can plug into 50 amp connections and split to two 30s.

Your collective wisdom in the advisability/usefulness on both alternatives would be appreciated.

[richinny]

there is a thread here on the forum somewhere that mentions frequent tripping of the 30a breaker in the 30/20 combination breaker. it stated that if the 20a circuit is on a heavily loaded circuit, the heat generated will contribute to the premature tripping of the 30a breaker. swapping the wires with a lightly loaded circuit of the same amperage will often resolve the issue.

[BeachHouse]

Interesting discussion. I have had the campground 30A breaker trip due to high load, but not the trailer.

[Wazbro]

Originally Posted by jupitorj

Interesting discussion. I have had the campground 30A breaker trip due to high load, but not the trailer.

There are a couple of common reasons for that.

1) A poor connection at the plug generates heat near the breaker and draws more power, either your plug having corrosion and needing to be cleaned (happens way to often) or outlet is worn or has corrosion (surprisingly happens less often).

2) Breakers tend to get weaker as they age and trip easier (partly caused by using the breaker as a switch as you should so the power is off when you plugin).

3) There is a plus or minus tolerance for when a breaker pops.

[afneill]

CalamonTin,
While I have not looked at RV services with 50Amp service, it is my understanding that all they do is take a 50Amp 240v receptacle and split that into two 120V circuits, each using the common neutral and ground, but having separate conductors for the hot wire. If you had two 30Amp panels in your trailer each could be fed from one of these circuits. Then you could separate the loads in your trailer into each of the panels, trying to balance them when you do.

You mention this occuring while the weather is hot. While we think of the heat necessary to trip a breaker being produced by the load on the circuit, other sources can contribute to the heat produced. Others have mentioned the 20Amp half of the twin 20-30Amp breaker being under heavy load, loose or corroded terminals, tripping at the pedestal in the campground and the weakening of the trip unit. Ambient heat can play a big role in causing a trip. If it is hot in your trailer, if the pedestal is in direct sunlight, especially a western exposure, or just about anything else that causes a higher ambient temperature will affect the load carrying capacity of a circuit breaker.

[jackbickel]

where can replacement circuit breakers be purchased? we have a 2000 Safari 25.

[TheGreatleys]

Originally Posted by jackbickel

where can replacement circuit breakers be purchased? we have a 2000 Safari 25.

Hardware store. Get the same brand/type and rating as the old one. Take a picture or bring the old one with you.

That said, why are you replacing a breaker? If it's tripping, it's probably doing its job. Your problem is more likely to be elsewhere.

[jackbickel]

Most likely its not the breaker, but wanted to know where one gets replacements. Wilma is in storage now- coming out next week for some trouble shooting. Thx for your reply.