MarkODonnell
New Member
- Messages
- 3
- Location
- Australia Sunshine Coast
Hi everyone
I have a problem with my Kemppi miniarc evo 200 mig welder.
I have had the welder since new and have used it a lot as I had a large steel 30 foot steel boat and I used it extensively to repair and renovate the boat.
Over the last 5 years I have used the welder sporadically. I turned on the welder last week and it started up as usual and after about 30 seconds the lights on the screen went out and the welder shut down. I unplugged the welder from power and plugged it into a different power socket, the welder powered up and then shut down 5 seconds later.
I opened the welder and discovered that when first plugged in it will power up for approximately 30 seconds then will power up for shorter and shorter times when subsequently powered up again and again.
I tested the A001 board and found the voltages were all present and correct when first powered on so the 24v, 27v, 15v and 5v were there however they disappeared slowly as the welder powered down.
I could feel heat coming from the main Z0001 board and discovered two thermisters R3 and R4 were getting very hot and after measuring the ac voltage across them discovered that R3 was heating up the most and effectively shutting off power to the welder by going open circuit and upon cooling would allow power to get through. the power seems to go to two IGFETS in a casing under a heat sink.
I took the IGFETS out and tried to test but was getting inconsistent readings when comparing to the Infineon circuit diagrams which I downloaded from the web.
I have reassembled the welder which still has the original fault. I spoke to Kemppi in Australia who were quite helpful but were unable to supply a service manual or circuit diagrams, they told me they normally just swap out the boards when they have this sort of problem the cost of a new board was over $1000 AUD. I would like to repair this and am looking for help or advice. I am a pensioner so don't have a lot of money to throw at this. I do have an electronics background so am not worried about doing the repairs myself.
I have a problem with my Kemppi miniarc evo 200 mig welder.
I have had the welder since new and have used it a lot as I had a large steel 30 foot steel boat and I used it extensively to repair and renovate the boat.
Over the last 5 years I have used the welder sporadically. I turned on the welder last week and it started up as usual and after about 30 seconds the lights on the screen went out and the welder shut down. I unplugged the welder from power and plugged it into a different power socket, the welder powered up and then shut down 5 seconds later.
I opened the welder and discovered that when first plugged in it will power up for approximately 30 seconds then will power up for shorter and shorter times when subsequently powered up again and again.
I tested the A001 board and found the voltages were all present and correct when first powered on so the 24v, 27v, 15v and 5v were there however they disappeared slowly as the welder powered down.
I could feel heat coming from the main Z0001 board and discovered two thermisters R3 and R4 were getting very hot and after measuring the ac voltage across them discovered that R3 was heating up the most and effectively shutting off power to the welder by going open circuit and upon cooling would allow power to get through. the power seems to go to two IGFETS in a casing under a heat sink.
I took the IGFETS out and tried to test but was getting inconsistent readings when comparing to the Infineon circuit diagrams which I downloaded from the web.
I have reassembled the welder which still has the original fault. I spoke to Kemppi in Australia who were quite helpful but were unable to supply a service manual or circuit diagrams, they told me they normally just swap out the boards when they have this sort of problem the cost of a new board was over $1000 AUD. I would like to repair this and am looking for help or advice. I am a pensioner so don't have a lot of money to throw at this. I do have an electronics background so am not worried about doing the repairs myself.