Replacing old/stock circuit breakers

[ValiantV]

Originally Posted by Lake-Effect

I read a couple of datasheets for the circuitbreakers made by Carling Switch (the manufacturer of breakers sold by BlueSea). In their mechanical specs both types I looked at (M series and A series, stuff rated at up to 50A) had endurance of 10,000 ON-OFF operations at rated voltage and current.

That's pretty reasonable over the lifetime of a yacht, seems to me. So I don't think it's a terrible decision by the yacht-makers.

I suppose if operating them as switches doesn't reduce their effectiveness as circuit breakers, then I see your point.

I guess I'm just going by the comparison of other mechanical devices with similar actions - like a sear and hammer on a firearm. Engaging and then forcing those parts to "trip" manually has to cause some wear.

Then again, age, vibration, heat and other factors likely can cause a breaker to not do its job when most needed. I've seen a fair number of home circuit breakers -not- trip when overloaded and creating a dangerous situation.

But yes, 10,000 on/off cycles would seem pretty robust.

Anyway, adding a switch vs changing out the style of breaker remains an option that I'll have to explore further.

[Stu Jackson]

Originally Posted by Stu Jackson

You use the push-to-break button to turn the WH on and off. That's what it is there for. They are NOT breakers, they are I/O switches ONLY.

RETRACTION CORRECTION

I was wrong. I went back to RTFM!!!

My manual shows the wh "button" as a 20A breaker.

That said, it has been working just fine for me for the past 18 years as an I/O switch, too.

[ValiantV]

Originally Posted by Stu Jackson

RETRACTION CORRECTION

I was wrong. I went back to RTFM!!!

My manual shows the wh "button" as a 20A breaker.

That said, it has been working just fine for me for the past 18 years as an I/O switch, too.

Dunno Stu,
Mine don't appear to do anything when you press them if they're already in. They just keep being in. If it's out - tripped - pushing it will reset it.

Dunno if your​ '86 C34 has different breakers than my '92 C30, and the manual is woefully terse on the subject, not having and description at all, just a notation on a schematic.

Who knows. Different supplier, different style, maybe mine is broke. (Maybe yours has an "undocumented feature" [emoji14] )

[Lake-Effect]

Originally Posted by ValiantV

I suppose if operating them as switches doesn't reduce their effectiveness as circuit breakers, then I see your point.

Then again, age, vibration, heat and other factors likely can cause a breaker to not do its job when most needed. I've seen a fair number of home circuit breakers -not- trip when overloaded and creating a dangerous situation.

But yes, 10,000 on/off cycles would seem pretty robust.

I haven't smashed a breaker apart recently, but I'm confident that operating them as a switch shouldn't diminish their effectiveness as a protection device. It might even be argued that a breaker that's manually cycled regularly would be in better condition than a breaker that's sat untripped and not cycled manually for years...

[ValiantV]

Originally Posted by Lake-Effect

I haven't smashed a breaker apart recently, but I'm confident that operating them as a switch shouldn't diminish their effectiveness as a protection device. It might even be argued that a breaker that's manually cycled regularly would be in better condition than a breaker that's sat untripped and not cycled manually for years...

Also a reasonable conclusion. Sometimes switches like to be "exercised" to keep the contacts clean and make sure that heat/dirt/age hasn't glued parts together.

[Stu Jackson]

Originally Posted by ValiantV

Dunno Stu,
Mine don't appear to do anything when you press them if they're already in. They just keep being in. If it's out - tripped - pushing it will reset it.

Dunno if your​ '86 C34 has different breakers than my '92 C30, and the manual is woefully terse on the subject, not having and description at all, just a notation on a schematic.

Who knows. Different supplier, different style, maybe mine is broke. (Maybe yours has an "undocumented feature" [emoji14] )

Here's a picture of mine.

AC & Power questions - Reverse Polarity Flix

The button works as an I/O switch. The manual says it's a breaker, but I should look behind the panel to confirm it.

It simply clicks in or ON and out for OFF. Sounds like yours isn;t working that way.

[ValiantV]

Originally Posted by Stu Jackson

Here's a picture of mine.

AC & Power questions - Reverse Polarity Flix

The button works as an I/O switch. The manual says it's a breaker, but I should look behind the panel to confirm it.

It simply clicks in or ON and out for OFF. Sounds like yours isn;t working that way.

Slightly different looking panel, but same idea.

Seen these before, but the ones I'm used to protrude from the panel enough to grab them an "pull" them off.

As I said, the manual is pretty slim on details. So whether mine are broken or some other choice is unclear. I suppose I could see if I can find a part number and look it up, but with 25 y/o breakers, not sure I'll find good info.

[ValiantV]

Originally Posted by Stu Jackson

You use the push-to-break button to turn the WH on and off. That's what it is there for. They are NOT breakers, they are I/O switches ONLY.

Accessories is for anything that is added to the A.C. power downstream. Look behind the panel and see if anything is connected to it.

Hey Stu,

My apologies. After getting back to the boat and trying some of the WORKING circuit breakers, I have found (as you suggested) that they do indeed, push-off and push-on as well as push to reset.

My toasted (looks more like old and corroded) CB that has failed no longer pushes to do much of anything.

Unfortunately, because of their orientation in the panel, I can't read the manufacturer or part number on them. Are yours any more visible, and/or does anybody have an idea what Catalina was using back then? (1992)

The friendly folks at West Marine (price gougers) only have DC breakers in this style.

[hellosailor]

IIRC there are two very different kinds of breakers. Thermal, and magnetic. Our usual boat breakers are thermal, and they have a limited number of cycles because they are designed as thermal fault breakers. Aircraft breakers are intended to be used as switches, and they use the magnetic breakers because those have a much greater life cycle. And those are normally "push button" instead of being thrown.

I wonder how many aircraft have on-board hot water heaters that need aviation grade breakers though. That's gonna keep me up all night.(G)

[Colin A]

Most boats today have a mix of thermal and hydraulic magnetic breakers onboard. The common Carling A series are Hydraulic magnetic for instance. Most of the push to reset I have seen are thermal.
Depending on the sizer of the hole in the existing panel you could try a Potter Brumfield W23 or W31 series breaker. They are rated to 240VAC, and are fairly robust. I may have some at work but I'm not sure I have any 20 amps.
http://www.farnell.com/datasheets/59...585.1493395112

At work we have been building panels with Carling and Airpax breakers for over 30 years, many being used for switching. On average when people call to replace a breaker I find their boats are 20-25 years old, which to me is a decent lifespan.

[ValiantV]

Originally Posted by hellosailor

IIRC there are two very different kinds of breakers. Thermal, and magnetic. Our usual boat breakers are thermal, and they have a limited number of cycles because they are designed as thermal fault breakers. Aircraft breakers are intended to be used as switches, and they use the magnetic breakers because those have a much greater life cycle. And those are normally "push button" instead of being thrown.

I wonder how many aircraft have on-board hot water heaters that need aviation grade breakers though. That's gonna keep me up all night.(G)

Yes, seen specs for both. Yes also, seems the boat breakers are thermal.

I'd have to check the Cessna manuals to see if those are "magnetic", but seeing as magnetism is unwanted anywhere near the compass, I'll bet those are thermal too.

[Wotname]

Originally Posted by hellosailor

IIRC there are two very different kinds of breakers. Thermal, and magnetic. Our usual boat breakers are thermal, and they have a limited number of cycles because they are designed as thermal fault breakers. Aircraft breakers are intended to be used as switches, and they use the magnetic breakers because those have a much greater life cycle. And those are normally "push button" instead of being thrown.

I wonder how many aircraft have on-board hot water heaters that need aviation grade breakers though. That's gonna keep me up all night.(G)

Sweet dreams, rest easy
Ever had tea or coffee on board?
If it was hot, it came outta a on-board water heater