What it is and where it fits
The Siemens 3RT2517-2FW40 is a SIRIUS contactor in frame size S00, meaning it's the compact footprint for light-to-medium motor and resistive loads inside a control panel. It mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 50022, so it integrates into a standard panel layout without special brackets. The contactor measures 45 mm wide by 70 mm high by 73 mm deep, which slots into a standard 45 mm DIN-rail pitch. Side-by-side mounting is allowed, with a 6 mm clearance needed at the side for arc dissipation — no extra gap between units if you stack them tight. Mounting position is flexible: the contactor can be rotated ±180° on a vertical surface and tilted forward or backward by ±22.5°, which helps when fitting into a crowded gland plate or a swing-frame sub-panel.
Termination and wiring
Both the main current circuit and the magnet coil use spring-type terminals — no screw torque to verify, no vibration loosening. The main circuit accepts 2x (0.5 to 4 mm²) solid or stranded wire, which covers most control-circuit and small-motor feeder sizes up to about 4 mm². The contactor includes an auxiliary switch block, with switching ratings spanning from 10 A at 24 V and 230 V down to 0.1 A at 600 V. That covers both 24 VDC PLC-level signals and 230 VAC pilot-duty circuits off the same set of contacts.
Operating conditions and endurance
Rated for operation from -25 °C to +60 °C, with storage down to -55 °C. Mechanical life is 30,000,000 operating cycles typical, and the AC-1 maximum switching rate is 1,000 operations per hour.