SIRIUS Power Contactor for Motor and Resistive Loads
The Siemens SIRIUS 3RT1034-1BB44-0AA1-ZX95 is a size S2 power contactor with a 24 VDC coil, designed for switching motor loads in industrial control panels. Its AC-3 rating delivers 18.5 kW at 500 V and 10 kW at 690 V, covering common three-phase induction motors in that power band. The AC-4 rating of 29 A at 400 V handles reversing or inching duty where the contactor makes and breaks stalled-rotor current.
Mounting and Panel Integration
Mounts via screw fixing or snaps onto a 35 mm DIN rail per DIN EN 50022, with side-by-side mounting permitted for dense panel layouts. The 55 mm width and 179 mm depth fit standard S2 contactor footprints; the 112 mm height leaves clearance for auxiliary contact blocks above. Screw-type terminals on the main circuit accept stranded conductors up to 2x 25 mm², solid conductors up to 2x 4 mm², and a minimum of 16 mm² at 40 °C ambient.
Switching Performance and Coil Data
The 24 VDC coil draws 10 A at rated voltage, with an arcing time of 10 to 15 ms and DC dropout delay of 20 to 30 ms. Maximum mechanical switching frequency is 10 million operations. Electrical endurance varies by duty: 1,200 operations/hour at AC-1 (resistive), 1,000 at AC-3 (motor running), 750 at AC-2 (slip-ring motor), and 250 at AC-4 (plugging/reversing). Coil suppression is internal; for inductive loads downstream, verify free-wheel diode polarity.