Mains supply is 415 V, single phase (2 1ines of 3 phase supply) 50 Hz; air operation - spring follow-double acting cylinder - air line filter, lubricator, electric solenoid valve regular pressure gauge; machine mechanically capable of 125 operations/minute; electrical - foot switch/palm button - weld/no weld switch; pressure switch; transformer in Class "F" insulation, provided with 8 current regulating taps between 55% and 100% output; control circuits at less than 110 V; cooling - by water with separate circuits for main transformer, secondary conductor and electrode die (in case of projection welders) thyristors; each circuit to terminate in sight cup provide; wheel valves each circuit protection - transformer, thyristors by thermostat against water failure; luminous overload indicator on panel; and electronic controls: microprocessor based solid state electronic control with thyristor contactor unit.