Thermal circuit breaker problem

[Shoalwaters]

The 50 amp thermal circuit breaker on my starboard house battery trips about once every couple of weeks for no apparent reason and with little or no load on it. If I try to provoke it by switching on house lights, nav lights, bilge pumps, fridge etc, it doesn't trip. Can anything other than an electrical overload cause these things to trip?

[Jay N]

How old is it?

I recall that Blue Seas had a recall on an earlier model, although it may not be related to*your problem.

When the breaker opens, can you feel any heat coming from the switch?

Do you have a backup that you can test?

If it has been tripping frequently, it will generally be more likely to trip in the future, so trying out a new one might be the easiest/cheapest solution.

Double check that it is the proper size for the application, 50A isn't that much if you have large loads on that side.

[Shoalwaters]

Thanks J; your insights appreciated. It does look like some of the Blue Seas units, although there is no manufacturer's name on it. As noted, I cannot provoke it into tripping using normal loads. As you suggest, I will swap it over with the identical port side thermal breaker (which does not trip). That will tell me if the problem is with the breaker.

[rwidman]

Shoalwaters wrote:
I will swap it over with the identical port side thermal breaker (which does not trip). That will tell me if the problem is with the breaker.

That's how to troubleshoot a problem.*

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