Repairing a "Digital" Battery Charger like Exide


Several years ago I bought a "broken" battery charger at a garage sale, hoping that there was some internal fuse I could replace to make it run again.
I found out there were no fuses, but with some help from folks that did understand electronics I managed to identify and replace the blown voltage controller.
This has been the best battery charger I've ever had - so I was real disappointed when I tried to use the "car start" option and blew it up again.  This time I took some pictures so other folks might be able to fix theirs.


Here's my charger.  I tried to use it to jump start my motorcycle and it quit again.  Time to fix it!


Here's what the inside looks like.  12 volts comes out the bottom (which is over to the right).  Sorry about the blurry photo.


Now here's a photo to be proud of.  See that three pin power component on the heat sink?  THAT little bugger is what delivers the power to the battery!  The original component was rated at 55amps, but the best I could find was rated at 30amps.  I know now not to try to use it as a starter again.  The component that this charger used cross referenced to a "NTE5460". I use the NTE components because they have them hanging on pegs at the Fry's a couple of blocks from my house.  Other chargers may use different components, so cross reference your own part.  Not cheap though, the part was almost $7!

Added JUNE 2012 - had my motorcycle battery short internally during the night and came out to the charger showing neither orange or green lights.  Guessed rightly that it had managed to burn up the SCR chip again.  Found that NTE has discontinued the 5460, and while there seem to be a few available online they weren't on the wall at Fry's any more.  Closest that I could find was the NTE5465. Seems to work, but it is only rated at 10 amps and working a component at it's full rating is asking for failure.....   We'll see how long it lasts.

I disabled the "car start" option on my charger since it obviously isn't really up to the abuse that both the original owner and myself submitted it to.

Charging away.  This is the most effective battery charger I've ever had, but I'll still keep an "analog" one around just in case!
Now go fix yours!

Here's something I learned as a mechanical kind of guy messing with electrical stuff.  It's always the little three pin component mounted on a heatsink!
Worked for TVs, VCRs, amps, battery chargers, and a bunch of other stuff.  The reason they're on the heatsink to begin with is that they're having to work hard.