G= 220 V 50/60 Hz H= 380 V 50 Hz K= 600 V 50 Hz M= 230 V 50 Hz N= 401 V 50 Hz O= 415 V 50 Hz W= 240 V 60 Hz X= 480 V 60 Hz Z= 365 V 50 Hz K= Open S= NEMA 1 R= NEMA 3R J= NEMA 12 L= NEMA 4 D= NEMA 4X (J, L and D 65 kAIC, 1200 A and Below Only) U = UL Listed R = UL Recognized X = No Listing Maintenance Bypass (600 Vac) (100 – 1000 A) MB