Battery charger

Decided to try taking apart my battery charger, some kind of ancient and gigantic Japanese monstrosity which is way too big for its 20A max output, to see if I could find some burnt-out component or internal fuse or something to explain why it’s not charging anything.  (The main fuse is fine.)  The internet suggests a bad diode as the likely culprit.  Here’s the charger:

However, it’s not very take-apartable.  I got the front panel off but to really take it apart enough to get a good look at the electronics would require more patience and time than I have today.  I asked the marina to borrow a charger for a few minutes just to confirm that it is in fact the charger having problems and it’s not some massive coincidence whereby none of my batteries, new or old, all full of water, are accepting a charge.  Unfortunately there was a lot of bureaucracy involved and there were no chargers available right now anyway, so I gave up on that.  I went in the marina’s chandlery to see if they had any chargers and they didn’t, so I gave up on addressing the battery charger problem for today and decided the solar panels would have to do for now.

But then the chandlery sent me an SMS that yes, in fact, they did have a 12V 8A charger for S$80.  8A isn’t really enough for long term use but it’s fine for now, and S$80 is pretty cheap.  I figure it’ll be useful to have a backup charger anyway, even when I have a built-in one as part of the new electrical system; and this one is about 1/3 the size of my old one:

It works fine and is currently charging a couple of the new batteries:


Filed under electrical, photos, shopping

2 Responses to Battery charger

  1. Lee

    I enjoy reading your blog, keep up the good work. Though it makes me fearful that our boat is going to have increased corrosion problems in a tropical environment.

    Also, do you know about tef-gel or similar corrosion inhibitors for stainless fasteners in aluminum? And also that you want to use tinned copper electrical connectors and wire and not aluminum? That’s about all that I can think of.

    • Kris

      Thanks and ditto, I am really jealous of the adventures you’re having these days!

      I do think the tropical environment is probably more conducive to corrosion, because it’s so humid. I didn’t know about tef-gel but yeah, I do know about tinned copper and will make sure all the new wiring I’m doing is with tinned copper. It’s hard to find tinned copper wires and terminals here though, but I’m sure marine electricians should be able to get their hands on it. For stuff like the stereo I just wired, you don’t really get the option since the wiring harness it comes with is just stranded copper, but it’s probably ok if you solder the connections, since soldering is essentially tinning. I made sure to cover the entire splice in solder.

      I have found occasional small corrosion problems but I think they’re not all that prevalent when compared with other wiring issues. For example, the last owner did a crappy job of wiring some of the cabin fans; when I pull the wire tight the voltage increases, but normally it’s loose and the fan runs slow. So, I’d say not to worry too much about corrosion and instead focus on good wiring.

      Also the battery charger was ancient, I doubt it was corrosion that killed it so much as just age.

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