Circuit Breaker lifespan

[zboss]

Foks,

Do circuit breakers have a lifespan? I'm not talking about them not turning on or refusing to remain on...I've had two on our boat that eventually would not engage.

I'm referring to circuit breakers failing to perform their jobs, not tripping when they should.

Should I at least replace my 27 year old main AC circuit breaker?

Are there any reasons to upgrade to new circuit breakers? Our circuit breakers are the standard A-series style.

Thanks!

[redsky49]

In the world that exists outside of boats, there have been several cases where circuit breakers are known to fail to operate - Federal Pacific being one of the more well known examples.

In the marine environment, even with regular exercising of the breakers, I would be very vigilant of all safety devices, breakers and fuses.

[DeepFrz]

It might be a great time to replace with an RCD/GFCI. Whatever they are called.

[Andina Marie]

In particular, circuit breakers that are also used as on/off switches slowly suffer wear on the trip mechanism. The effect is to lower their trip level (so far as I've experienced). Presumably the trip level could get so low that they won't latch on.

But I've only seen this on breakers doubling as a switch, the trip level in a static breaker should not change.

[pesarsten]

I have seen many breakers that have failed as a result of normal usage. All would either trip without reason or fail to set. That doesn't mean that they can't fail to trip when overloaded.

If you want GFCI breakers, I would not install one as the main, rather install them on the branch circuits. This way WHEN you have a problem, and need to chase down what is causing the tripping ( possibly nuisance ) you will still have power to the rest of the circuits.

[exMaggieDrum]

Circuit breakers can and do wear out. Not only in marine use but also in a house. But on boats they get "cycled" on/off more frequently. I always carry spare c/b's for my panels in the variety of amp ratings that I have in the panel. Hopefully all your c/b's will trip upon overloads like they are supposed to. Nuisance trips and failure to turn on are usually the only indication you have of a problem though.

But - always, always check for loose wiring at the connections. I have replaced more than one melted c/b that was due to a loose connection.

New panels are bloody expensive though. If you do go that route, look at the ones by Blue Sea. There are other good ones too.

[zboss]

Originally Posted by exMaggieDrum

New panels are bloody expensive though. If you do go that route, look at the ones by Blue Sea. There are other good ones too.

Holy cow! I know... I looked at one of the Blue Sea Systems and nearly had a heart attack. Something like 2K!

We don't need a new panel and we are not generally having problems. We have also had to replace a fee breakers so we keep two of each size we need on the boat.

While we are in an area we can do work and [since we have an open-ended departure date] we are trying to compile an exhaustive list of what-ifs. Basically assuming everything on the boat will break at least once and probably in ways that we have not even considered.

We had a comedy of errors on our last trip to the Bahamas and when we look back we came to the realization that the majority of issues we experienced were due to decisions made well before we ever left - MONTHS before. Which cascaded into the Captain (me) making even worse decisions when crap hit the fan.

We got through the issues without requiring assistance but it ruined the first month of our cruise and cost lots more money than anticipated.

Trying to fill that black box with chips and I happen to be here wasting time on the internets with my circuit panel staring at me.

[JPA Cate]

zboss, replace the ones you use as on/off switches as soon as convenient. Carry spares for the rest. You've no way of knowing how previous owners used them, and may not be able to determine which ones have already been replaced. But once you've done yours, note it in the log book you keep of jobs done. It's really convenient to keep a record of what you did when. Can put receipts for warranteed items in it, too.

Cheers,

Ann

[exMaggieDrum]

Zboss, you're doing the same as I would. But I had to replace the AC panel as the previous owner had had a fire (or serious smoke at least) behind the panel that the survey didn't pick up so I decided to redo the AC panel. But the wiring behind the DC side was so kludged that I decided to redo that to. (I am/was a marine electrical tech so it was bothering me on my own boat. E.g. the cobbler has no shoes....).

So - I found that it became one of the things I was most proud of on the boat and I got a sense of joy every time I looked at it and knew it was the best it could be. But one way to really tidy things up (if it matters to you and/or just needs it) is to put a long row(s) of term strips behind the panel and put all the wires that go out to the devices on the boat, one terminal for each circuit breaker plus any for alarms, switches, whatever. Then take all the wire from each breaker and run it to the term strip. You should have extra wire which you can use to "tidy" the runs up, label each wire, etc. Then run new wire from the term strip to the breakers, using enough to allow nice tidy bundles and layout. It can really clean up decades of fixes and poor wiring without changing the panel itself. And if you ever decide to replace the panel then most of the work is already done.

But that would be silly unless it mattered to you like it did me. I hate nasty wire runs and will be redoing a lot on my new/old boat in the next year or two. One side benie though - you learn some interesting things by poking around with all that in thorough detail.

[Cheechako]

I've had a surprising number do what yours have done. Not stay on or trip too easy. So I would say yes they do have a lifespan, and it's shorter than non marine types for some reason!
BTW, used marine equipt stores are a good source, they often have a big area of brand new breakers purchased from out of business boat builders etc.


I often wonder if those fancy breakers are as good as just switches and fuses. It ought to be a lot cheaper to go that way on a new panel build!


and interestingly, a number of small boats we built for the US Marine Corps required fuses by specification. simple, reliable and can be replaced in seconds not hours.