SIRIUS Size S00 power contactor, 24 V DC coil
The Siemens 3RT1017-2HB42 is a SIRIUS power contactor in the Size S00 frame, designed for switching motor loads and resistive loads in control panels. It mounts via screw or snap-on onto 35 mm standard mounting rail per DIN EN 50022, fitting into the compact 45 mm width slot common in panel layouts. The magnet coil is rated 24 V DC, with a closing power of 2.3 W and holding power of 2.3 W — a DC-energised coil that stays latched on steady DC without the AC hum or inrush spike. Rated operational current at AC-12 (resistive) is 10 A at 24 V, and at AC-2 (slip-ring motors) it delivers 5.5 kW at 400 V. Main circuit connections use spring-loaded terminals, accepting 2x (0.25 to 2.5 mm²) solid or stranded conductors, or 2x (24 to 14 AWG). The IP20 finger-safe enclosure on the front and terminals suits installation inside a closed panel where no washdown or dust ingress is expected.
Coordination and short-circuit protection
For type 2 coordination (no damage to the contactor after a short circuit), the required upstream fuse is gL/gG 20 A. Type 1 coordination allows a 35 A gL/gG fuse, where the contactor may need replacement after a fault but the circuit clears safely. This distinction matters when specifying the panel's SCCR and selectivity with downstream motor starters. Degree of pollution 3 per IEC 60947-1 means the contactor is rated for conductive pollution environments typical of industrial enclosures — not clean-room or sealed electronic cabinets. Altitude rating extends to 2 000 m without derating.
Environmental and mechanical limits
Operating temperature range is -25 to +60 °C, covering most indoor industrial environments without forced cooling. Side-by-side mounting is permitted — the 6 mm spacing at the side is the minimum air gap for heat dissipation when multiple contactors are ganged on the rail. Mechanical endurance is rated at 30 million operations typical, reflecting the SIRIUS family's design for high-cycle applications like conveyor or pump cycling.