SIRIUS Size S2 Power Contactor — 3RT1035-1BB44-ZM96
The Siemens 3RT1035-1BB44-ZM96 is a SIRIUS power contactor in the Size S2 frame, rated for motor switching at 22 kW at 500 V (AC-3) and 18.5 kW at 400 V (AC-2), with an AC-4 breaking current of 35 A at 400 V for reversing or inching duty.
Ratings and Duty Cycles
AC-1 resistive switching supports up to 1,200 operations per hour, while AC-3 motor duty allows 1,000 ops/h. The more severe AC-4 category (plugging, inching) is rated at 300 ops/h, reflecting the higher electrical stress on the contacts during reversal or jogging.
Pollution degree 3 (conductive pollution, typical for industrial control panels) is specified, so no additional conformal coating is required for normal factory-floor environments. RoHS compliance date is noted as May 1, 2012, indicating the part meets the EU RoHS substance restrictions effective from that date.
Main circuit terminals accept solid or stranded conductors: 2x (0.75 to 16 mm²) for the power path, with a minimum permissible cross-section of 16 mm² at 40 °C for full-rated current. Auxiliary/control terminals accept solid wire: 2x (0.5 to 1.5 mm²) and 2x (0.75 to 2.5 mm²), with a maximum of 2x (0.75 to 4 mm²). Stranded terminations on the control side accept 2x (0.75 to 25 mm²). Dimensions: 112 mm height, 55 mm width, 179 mm depth — the depth is the key constraint when fitting into shallow enclosures or behind gland plates.