The Siemens 3RT1017-1BF42 is a SIRIUS power contactor in the Size S00 frame, built for switching motor loads in control panels. It snaps onto a 35 mm DIN rail per DIN EN 50022 and uses screw-type terminals for the main circuit. The 110 V DC coil pulls in at 85 % of rated voltage and holds at 3.3 W DC, so it's a straight fit for a 110 V DC control bus — no dropping resistor needed.
Ratings and what they mean for the panel
The AC-1 resistive rating is 10 A, but the motor-duty numbers are what drive the selection. At 400 V AC-2 it handles 5.5 kW; at 400 V AC-4 it's rated 8.5 A — that's the heavy inching/plugging duty cycle. At 500 V and 690 V it still carries 5.5 kW, so it covers 400 V to 690 V three-phase motors without derating the power. The 24 V DC rating is 10 A, 60 V DC is 2 A, 110 V DC is 1 A, and 230 V DC is 0.3 A — these are the DC switching limits for resistive loads; inductive DC loads need a diode or varistor across the coil. Mechanical endurance is 30 million operations, so it's rated for high-cycle applications like conveyor diverters or packaging machinery. The operating temperature range of -25 to +60 °C covers most indoor panel environments without derating. Pollution degree 3 means it's suitable for industrial atmospheres with conductive dust or occasional condensation.
Mounting and wiring
The contactor is 45 mm wide, 57.5 mm tall, and 72 mm deep — that's a standard Size S00 footprint that fits alongside other SIRIUS components on the same DIN rail. Side-by-side mounting is allowed without derating, so you can gang multiple contactors in a row. The screw terminals accept 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or max 2x (0.75 to 4 mm²) solid or stranded wire. AWG equivalents are 2x (20 to 16), 2x (18 to 14), and 1x 12. The IP20 front and terminal protection means it's finger-safe once installed in an enclosure.
Coordination and protection
For Type 2 coordination (no damage to the contactor after a short circuit), the required upstream fuse is gL/gG 20 A. For Type 1 coordination (contactor may need replacement but the circuit is safe), the fuse is gL/gG 35 A. These are the values for the main circuit; the control circuit should be fused separately per the coil rating.