Siemens SIRIUS 3RT1025-1BD40-1AA0 — Power Contactor, S0 Frame
Rated for AC-4 duty at 15.5 A at 400 V, this contactor handles the severe switching conditions of reversing or inching motor starts where the contacts close under full load. At higher line voltages, the motor power rating reaches 10 kW at 500 V and 11 kW at 690 V, making it suitable for 690 V distribution systems common in mining, marine, and heavy industrial installations. Auxiliary contacts are rated for 10 A at 24 V, 6 A at 230 V, and 3 A at 400 V — enough for PLC inputs or indicator lamps on the same panel.
Side-by-side mounting allowed; 6 mm clearance recommended. Screw terminals accept solid conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), max 2x (0.75 to 4 mm²). For stranded wire: 2x (1 to 2.5 mm²), 2x (2.5 to 6 mm²), max 2x 10 mm². AWG equivalents: 2x (16 to 12), 2x (14 to 10), 1x 8. Strip length and torque values follow standard Siemens S0 practice. IP20 on the front protects against finger contact; the terminals themselves are IP00, so the contactor must be installed inside a panel or enclosure with a higher overall IP rating.