Lifespan of a batteryswitch?

[blaubart]

got some electrical work done which involved installing fuses at the batteryswitch. Now when the switch is in both position, it will only charge the starter battery, not the housing battery as it has done before. The sparky told me that the switch might be on it's way out. Not sure how old the switch
is, but do they wear out after a while? It just seems to be a strange coincidence that it happens to fail after he was working on it.

Any ideas?

Thanks

[Ex-Calif]

How old is the switch? They definitely don't last forever but they should last a long time.

If the switch is connecting both banks in parallel when set at both, it seems almost impossible that both batteries won't charge.

If he is telling you that the switch is the cause of the charging issue, I would be suspect.

[blaubart]

when the switch is on both, it charges only the starter battery. I will have to switch to pos 1 to charge the housing battery. Yeah, I am suspicious too, but what can I do? The switch could also have a genuine fault.

[Ex-Calif]

Well that's the issue. When you set the switch to both, you are basically putting all the batteries in parallel. If you are able to get juice "out" of the house on "both" then juice must be able to get in.

Unless I am missing something pretty basic.

[jscott]

Sure sounds like he screwed up the wiring to me.

I would rmove the cables at the batteries at get out an ohm meter, to see what he did.

Then show him and watch him fix it or don't pay.

[jscott]

Oh, and a visual inspection of the back of the swicth should show any severe arcing that may have occurred.

Or just watch for heat build-up when charge a dead set of batteries.

[Lancerbye]

I would get a second qualified opinion. Your sparky could be right but when coincidences like that happen. I get a bit suspicious. When a piece of equipment fails after someone has just worked on it, well......

[hellosailor]

Pretty much every switch, every "contactor", every "plug" has a rating in life cycles. The typical Centronics Parallel Printer Plug that was standard with computers for so many years? Was rated for less than 500 cycles, i.e. unplug it twice every day and it would be unreliable by the end of the year--even if many of them beat that rating.

So if your battery switch was made by a good company, and used within the ratings supplied, and had no defects....they can tell you how many cycles it was good for but that generally is "an awful long time" for recreational boaters.

Some companies had a problem with switches overheating, literally metling and failing. There have been product recalls, check your vendor for that too.

"When a piece of equipment fails after someone has just worked on it, well......"
I feel the same way, but also note that if a piece of equipment has just been hanging on (i.e. case or contacts distorted from heat) sometimes "even the best butter" isn't good enough, any touching it will cause it to fail.

I'd double-check the job, check with the switch maker (for ratings and recalls) and if there's no easy answer--replace it with a heavy duty switch from a prime maker.

[blaubart]

well, the sparky went back to the boat and rechecked what he had done. And last Saturday, he called me to say that it is all working again. Looks like he learned a new lesson. Maybe I should ask for a discount on his rate. Anyway all looking good now. Thanks all for the comments.

[hellosailor]

Not to say my reading comprehension must be a tad slow...but how did installing fuses at the battery switch affect isolating the two batteries during charging??

[David M]

To test your battery switch(s), disconnect all of the terminals from the battery switch and put an ohm meter across the switch terminals and test all the different possibilities. You should either get infinite resistance or zero resistance (or a tiny fraction of an ohm). Anything else is unacceptable and you should replace your old battery switch with a new one.

[blaubart]

he reckons one terminal must have moved when he tightened the screws

[drh1965]

Originally Posted by hellosailor

Not to say my reading comprehension must be a tad slow...but how did installing fuses at the battery switch affect isolating the two batteries during charging??

Sounds more like diodes to me...