Miller plasma cutter help

I forgot to mention that no air comes out of the torch either. So, if you squeeze the trigger with the machine on and air plugged in, nothing happens.

Josh

Josh wrote:

I've been through those pieces a few times and they are in pretty good shape.

Thanks Jim.

Josh

Jim wrote:

If you have the manual there likely is a trouble shooting chart ... Miller also has manuals online. You need the exact model and serial. Randy

Does air come out when you turn the output control all the way to the left.? (Air pressure test)

Make sure your trigger is actually closing when pressed-a meter or continuity light will confirm this.

Miller plasmas, with their never ending safeties are a pain. Among the most tempermental of plasma cutters out there.

Many of these safeties revert back to the circuit board.

From my experience, it could be a safety or, more probably, a circuit board problem.

Good Luck brad

Thanks, I'll give that a try tomorrow. Jim forwarded me a link to the manual and for my problem, it only says to take it to a Miller repair center,etc. I'll mess with it more tomorrow and see what happens.

Josh

Jim wrote:

Could be a bad switch in the torch head, or a broken wire in the cable. Unfortunately, it is probably the control board, though.

They use little tiny chip FETs to sense and condition the control inputs. One of them may be toast. This would be a moderately simple repair if it weren't for that infernal conformal coating they use on the board. A new board is about $250.

My plasma had a similar problem. I did attempt to repair the board (and I repair surface mount equipment for a living), but that coating defeated me. By the time I managed to chew through it, I'd mangled the traces on the board. So I bit the bullet and bought the replacement board.

Gary