A friend asked me to have a look at his broken welder, after having a look himself. It's pretty much the same as my Clarke Pro90.
It's a typically 'well-used' 25 year old welder...with a Sealey Mightymig torch fitted.
Powers up with the fan running. No torch action.
Had a look inside for the usual type of faults and cleaned all the connection. Nothing found.
I reconnected the motor's red wire to the correct place on the bridge rectifier (he'd removed this wire), DC +, Nothing doing.
Dismantled the torch. It was in unusually really good condition. No probs there, continuity to the board was fine.
There's no fuse on the board, it seems.
I tested the 240 to 24 vac transformer. The output was fine, if a little high at 30 vac?
I then re-flowed a couple of suspect looking joints on the back of the board. No joy.
I took the casing off the relay - clean contacts and all seemed OK. Then it was bed time.
So it seems 24 vdc is not getting to the relay, is that suggesting the heat sunk rectifier on the right is broken?
Other components to check first, the diodes and transistors? Any other ideas?
Cheers folks.
It's a typically 'well-used' 25 year old welder...with a Sealey Mightymig torch fitted.
Powers up with the fan running. No torch action.
Had a look inside for the usual type of faults and cleaned all the connection. Nothing found.
I reconnected the motor's red wire to the correct place on the bridge rectifier (he'd removed this wire), DC +, Nothing doing.
Dismantled the torch. It was in unusually really good condition. No probs there, continuity to the board was fine.
There's no fuse on the board, it seems.
I tested the 240 to 24 vac transformer. The output was fine, if a little high at 30 vac?
I then re-flowed a couple of suspect looking joints on the back of the board. No joy.
I took the casing off the relay - clean contacts and all seemed OK. Then it was bed time.
So it seems 24 vdc is not getting to the relay, is that suggesting the heat sunk rectifier on the right is broken?
Other components to check first, the diodes and transistors? Any other ideas?
Cheers folks.