Requirements for North American market according to UL and CSA standards Suitable For Use On A Circuit Capable Of Delivering Not More Than X rms Symmetrical Amperes, Y Volts Maximum. . Motor power X Y HP Amperes Volts 1 to 5 HP 5000 A 240 V 3-phase 200 to 240 V 7.5 to 40 HP 5000 A (1) 240 V 3-phase 380 to 480 V (1) May be rated 22000 A Do not use with rigid conduits.