Okay, since you say it's an older unit, I'm going to take a risk and assume it's not an inverter rig. Thus, it has a transformer. If the thing is blowing the fuse the moment you strike an arc (pull the trigger), but not when you first turn it on, then the transformer is probably okay. The most likely cause is then a short between the contact tip and ground, after the contactor relay. So, I'd say it's time to replace the liner, the adaptor and the tip, and check the wiring in the handpiece while you're in there, just to make sure you don't have any cooked insulation that might be exacerbating the problem.
Best guess I can come up with, Will. Hope it helps.
Okay, since you say it's an
Okay, since you say it's an older unit, I'm going to take a risk and assume it's not an inverter rig. Thus, it has a transformer. If the thing is blowing the fuse the moment you strike an arc (pull the trigger), but not when you first turn it on, then the transformer is probably okay. The most likely cause is then a short between the contact tip and ground, after the contactor relay. So, I'd say it's time to replace the liner, the adaptor and the tip, and check the wiring in the handpiece while you're in there, just to make sure you don't have any cooked insulation that might be exacerbating the problem.
Best guess I can come up with, Will. Hope it helps.