What it is and what it does
The Siemens 3RT1017-2BG41 is a SIRIUS power contactor in frame size S00, designed for switching motor loads in control panels. It mounts via screw or snap-on onto a 35 mm DIN rail per EN 50022, so it integrates into standard panel layouts without adapters. The main circuit uses spring-loaded terminals, accepting 2x (0.25 to 2.5 mm²) solid or stranded wire — no screw torque to check, which speeds up wiring on repetitive builds. Its AC-2 rating at 400 V is 5.5 kW, covering wound-rotor motor loads where starting current is moderate. For plugging or inching duty (AC-4), the rated operational current is 8.5 A at 400 V — the figure that governs frequent reversing or jogging applications.