Sterling Marine Battery Charger

[Seahorses]

I have a 24 Volt 25 amp Sterling battery charger. It is about 3 years old and never had any problems, until last weekend. The charger has 2 x 24 Volt outputs and these have been connected to the 2 pairs of batteries, one start only and the other start/domestics. the latter pair having been replaced a couple of weeks ago with new.

Last Saturday night the charger was making a buzzing noise and when checked it out the start batteries which are about 6 or more years old were really hot and it seemed like the charger was overcharging, the output to the new batteries were fine.

Im now not sure if the charger is at fault or if its the batteries. Does any body know how I can check the charger, what voltage should be shown on the output terminals without batteries being connected and what needs to be shown when connected to a 24 volt system and under load. Will the charger only start the charging cycle when conected to batteries.

 

[Divemaster1]

Think you should have about 27V at the terminals from the charger ...

And after 6 years, I would expect your batteries to be faulty ...

 

[Barry Jones]

Put a meter on the starter battery terminals when charging and measure the charging voltage !!

Try charging the starter battery on the alternator only - do you get any problems ?

Is the starter battery holding charge and behaving otherwise (i.e starting the engine briskly) ??

 

[Seahorses]

Not had a problem with the start batteries and always charged ok from the alternator, however being old I know they can suddenly start showing faults.

Ive got the charger at home and need to check it all out, so any other advice would be appreciated.

 

[Barry Jones]

Measuring an off load voltage won't tell you much, although you could try that to see if its unusual.

Can you try it on another lead acid battery at home ?

 

[BGW]

Im now not sure if the charger is at fault or if its the batteries. Does any body know how I can check the charger, what voltage should be shown on the output terminals without batteries being connected and what needs to be shown when connected to a 24 volt system and under load. Will the charger only start the charging cycle when conected to batteries.

Would it have been simpler just to swap the outputs over to see if the problem stayed with the suspect batteries or not?

 

[Andrew_Fanner]

Ring/email Mr S, he's very helpful if you talk sensibly.

 

[dingdongs]

you could also get the (sg)specific gravity checked out on your batteries but i would just purchase another pair and call it wear and tear as they've earn't their keep.