Transformer repairs (Melb)

[MartyJ]

Hi guys,

A little off topic (pinball)...Basically a mechanic mate has an old dinosaur of a battery charger, which had an unfortunate accident with the apprentice...Hooked up the wrong polarities on a car batt to charge and it killed it. 

He want to keep it as it charges car batteries like nothing else....I've had a look and cannot see anything obvious..Given its 240v I'm not touching that side of things at all.  I have attached a couple of photos of the internals...I'm guessing it may be the transformer - in which case is there anyone in Melbourne that can fix them?

Also, out of interest, what is the purpose of the metal plates which sit at the back (wires from transformer out goes to them?

Thanks guys

[The pinballist formally known as Dean Morgan]

The metal plates appear to be heat sinks to disipate the heat on the bridge rectifier (although this is hard to confirm for sure from these photos).  Basicly it looks like the transformer simply steps down the voltage from 240vAC to 6 or 12v dependant on the setting of the front switch.  It would then pass through the bridge rectifier to be made into direct current (DC) output.

IT maynot be the transformer that is faulty, you need to have this tested by someone with electrical knowlage whom can use a multi meter etc.  Is there any fuses on the unit?  It may be that you have output from the transformer and that the bridge rectifier is stuffed.

[MartyJ]

The small silver box connected in the lower section is aparently a 'circut breaker'...There was an old one on there and he replaced it after the mishap.

[arcadoz]

Where the o/p of the transformer is connected between the plates/heatsinks, there are four "press in" diodes of which one or more might be blown, more likely than the transformer.
If they need to be replaced they can be pressed out in a vice with a short tube and a drift of some sort.

[MartyJ]

Where the o/p of the transformer is connected between the plates/heatsinks, there are four "press in" diodes of which one or more might be blown, more likely than the transformer.
If they need to be replaced they can be pressed out in a vice with a short tube and a drift of some sort.

Ok...That makes sense too!....The trouble will be finding replacements if they are toasted!...

I just want to check everything before I power it up as I dont want to toast my switchboard either...

[The Black Knight]

That is one very old linear battery charger. Personally, I wouldn't bother fixing it as battery technology has come a long way since that was made. I work for a company that manufactures battery chargers and as your friend is a mechanic, I would recommend a new 4 stage duel voltage charger. If he's interested in a new charger, drop me a PM.

Regards,

The Black Knight.

[MartyJ]

That is one very old linear battery charger. Personally, I wouldn't bother fixing it as battery technology has come a long way since that was made. I work for a company that manufactures battery chargers and as your friend is a mechanic, I would recommend a new 4 stage duel voltage charger. If he's interested in a new charger, drop me a PM.

Regards,

The Black Knight.

Howdee,They've had this one for a very long time.  They've had quite a few (ie Snapon and others) which aparently don't charge anywear near as quickly as this one (espically without any 'smarts')..however they have said if this ones DOA they will look at purchasing another one (I'll PM you then)..

CHeers