I had a meeting last night with the US plant.
Ourr test showed that the controller is very normal, we suggested the folliwing :
1. We cannot do more than this repair because no more replacement part available.
in market.
2. Send the controller back to you, you try it with correct correction.
3. If it is stiill unstable, we would suggest you just keep the machine as spare parts for another driller.
4. Please discuss with your management for a new system putchase SD 302C, I already quoted.
5. We are ready to send the controller back, please confirm me, then I can arrange the controller back.