My torchmate 4800 was working fine then all of a sudden it will not arc. All the consumables are attached and tight and I have over 100 psi coming to the machine. Not sure what else is wrong.
You would want to check the indicator lights on the front face of plasma cutter, if two bottom lights are lit then this could indicate an open circuit. Check the electrode on the machine torch that it springs back freely when you press it up with your finger. You can turn the amperage knob all the way to the left to purge air from the torch, ensure the purging pressure shown on the gauge is around 85 psi, adjust the regulator knob if low. If pressure will not increase while purging then ensure you have between 110 and 120 psi at back of plasma cutter.