carbon
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- Messages
- 3,085
- Location
- S. Glos. U.K
I have a thermal arc 250 ac/dc the suddenly stopped welding, no loud bangs, no magic smoke escaping from the case. Putting into stick mode resulted in a buzzing sound from the area of the transformer Taking the sides off to visually check didn’t result in anything obvious
Behind the pcb are igbt’s and diodes. After removing the pcb one of the diode was found to be faulty as it showed continuity in both directions. But still no visual signs of damage
Checking the component’s on the pcb more closely with a dmm I found one diode that didn’t show any reading in either direction so started to desolder it to find it was in two prices
I’ve replaced the diodes with slightly higher spec ones as the originals didn’t seem to be available and it seems to be welding again, not sure if I needed to do anything extra to determine if there’s a underlying fault or if it was a age related failure.
6mm 5083 aluminium plate
Edit. I should have mentioned it still had the hf start.
Behind the pcb are igbt’s and diodes. After removing the pcb one of the diode was found to be faulty as it showed continuity in both directions. But still no visual signs of damage
Checking the component’s on the pcb more closely with a dmm I found one diode that didn’t show any reading in either direction so started to desolder it to find it was in two prices
I’ve replaced the diodes with slightly higher spec ones as the originals didn’t seem to be available and it seems to be welding again, not sure if I needed to do anything extra to determine if there’s a underlying fault or if it was a age related failure.
6mm 5083 aluminium plate
Edit. I should have mentioned it still had the hf start.
