Trouble with Blackface Sa200

[Wannabe welder2727]

I have been welding with this machine for a few weeks with no problems. Then all of a sudden it quit welding. It ran a grinder but won’t strike an arc. It would idle up and still wouldn’t strike an arc. Now it won’t idle up when I go to strike an arc. I can manually idle it up and it will weld, just wondering if anyone had any ideas? Your help is appreciated!!

[Wannabe welder2727]

What’s funny is I have proper amperage at the positive/negative lugs. My ground? Bad connection at stinger? Any ideas?

[Wannabe welder2727]

Just checked the positive/negative lugs again, now it’s showing an open circuit. My welder is going berserk.

[duaneb55]

Could be failed main shunt coils or bad contacts on the coarse amperage selector switch or a broke copper strap to the coarse amperage selector switch or . . .

[Iron Beaver]

My SAE-600 did this exact same thing the other day. As it turns out the fine adjustment rheostat had burned up. I think it's labeled "Job selector" or something like that, but it controls the output voltage of the machine