The Siemens 3RT2037-1AB04 is a SIRIUS power contactor in the Size S2 frame, rated for 65 A at 480 V in AC-3 duty — the motor-switching curve that governs most induction-motor loads up to that current. The 24 V 50 Hz coil pulls in with a typical pick-up power draw, and the screw-type terminals accept 2x (0.5 to 1.5 mm²) solid or stranded, or 2x (0.75 to 2.5 mm²).
The 55 mm width and 114 mm height fit standard panel layouts; depth is 174 mm including coil and arc chamber.
Switching performance and mechanical life
Rated for 10 million mechanical operations typical. Maximum switching rates: 800 cycles/hour at AC-1 (resistive), 700 at AC-3 (motor), 400 at AC-2 (slip-ring motor), 200 at AC-4 (plugging/inching). Arcing time is 10 to 20 ms; closing time is 10 to 18 ms. Main contacts are rated for 18 to 1 utilization category.
Coil and auxiliary ratings
The 24 V 50 Hz coil draws 0.37 A at 50 Hz. Auxiliary contact ratings at various DC voltages: 6 A at 24 V, 2 A at 48 V, 2 A at 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, 3 A at 400 V, 0.6 A at 440 V, 2 A at 500 V. No auxiliary switch block is included on this base unit.