Hello good morning ... I am having a problem with a welding machine zx7-250 ... When you start welding immediately mark high temperature just by giving a little spark ... High temperature is not because the heatsinks are cold. The vacuum welder gives approx. 60v And the incredible thing is that depending on how the power is put on it is how it goes off or not ... I have the idea that it may be a fault in the control system but I don't know ... Any help is appreciated .. Thanks!