Introduction to two stage foot Pedal switch

When the two foot switches in the first stage switch is closed, the upper electrode welding head pressure to the workpiece, continue to depress 

the pedal, so that the second-level switch is closed, the trigger welding power supply-discharge welding, weld this if you wantto give up, do not 

the second level switch can be closed, release the first-level switch, theelectrode back to the starting position.