View Single Post
  #46   Report Post  
Posted to uk.d-i-y
Archibald Tarquin Blenkinsopp[_4_] Archibald Tarquin Blenkinsopp[_4_] is offline
external usenet poster
 
Posts: 1,110
Default Electronics help

On Thu, 01 Feb 2018 08:33:20 GMT, Harry Bloomfield
wrote:

ss used his keyboard to write :
Charger for a mobility scooter. One charger not working, I opened it up and
as per image below it looks like some kind of fuse has blown.
Text on the board looks like 3A/2500AR.

Can anyone confirm and identify what I would need to replace.
I have limitations on electronic stuff but could probably manage to solder
this part if I can find a replacement.

https://imgur.com/a/QTZ0e


From what I can see in the image, it looks like a wire ended fuse which
has exploded. That suggests a serious fault.

Also from what I can see, it looks like a fairly crude charger.
transformer, bridge, then possibly a relay switching the charge current
on and off, driven by a basic voltage across the battery sensing
circuit.


Cobblers!

One does not need an NTC thermistor in a "crude" charger.

I would have serious doubts that terminal Voltage plays a big part in
the control feedback. The control is via current monitoring so a more
stable source of reference would be needed.

There would be no piddly little rectifiers in a "crude" charger
either, they would be after the tranny and would need to handle a few
Amps, assuming the charge process was to take less than 24 hours.

Incidentally an exploded fuse is a fairly minor fault from a
diagnostics perspective. Generally a few seconds with a DMM will find
the problem.

As to what happens when the little plastic thing with legs = 3 is
found to be S/C, is a completely different story.

AB