SIRIUS size S00 power contactor, 24 VDC coil
The Siemens 3RT1017-1BD41 is a SIRIUS power contactor in the compact size S00 frame, with a 24 VDC solenoid coil drawing 3.3 W for both pick-up and hold. It is rated for motor switching in AC-3 duty up to 5.5 kW at 400 V, and carries the same power rating at 500 V and 690 V per the datasheet. The contactor snaps onto a 35 mm DIN rail per EN 50022 and accepts screw-type terminals for the main circuit.
What the ratings mean for your panel
The AC-3 rating of 5.5 kW at 400 V tells you this contactor handles a standard 3-phase induction motor up to that shaft power under starting conditions — the contacts are sized for the inrush and the breaking of the running load. For AC-4 duty (plugging, inching, reversing), the rated operational current is 8.5 A at 400 V, which is the figure to use when the motor sees frequent reversals or jogging. The DC coil consumes 3.3 W continuously, so the control transformer or PLC output needs to supply that without voltage drop below the 0.85 x 24 V pick-up threshold. Short-circuit coordination is specified: with type 2 coordination (no damage to the contactor), use a gL/gG fuse rated 20 A; with type 1 coordination (contactor may need replacement), the fuse can be 35 A. This lets the panel builder size the branch protection correctly for the required selectivity. The screw terminals accept solid or stranded conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), and up to 2x (0.75 to 4 mm²) maximum. AWG equivalents are 2x (20 to 16), 2x (18 to 14), and 1x 12. The contactor is rated for pollution degree 3, meaning it is suitable for industrial environments with conductive or dry non-conductive pollution. IP20 on the front and terminals means finger-safe but not protected against moisture — install inside a panel with at least IP54 enclosure. Mechanical life is rated at 30,000,000 operating cycles, which is typical for a size S00 contactor in light-duty switching. Side-by-side mounting is permitted without derating, so multiple contactors can be ganged on the DIN rail for multi-motor groups. Ambient operating range is -25 to +60 °C, and the maximum operating altitude is 2,000 m.