Siemens 3RT1025-1AC20 Three-Phase AC Contactor

Siemens Sirius 3RT1025-1AC20 is a three-pole AC contactor (frame S0) with a 24 V AC coil, designed for compact motor control in AC-3 service. It is rated for up to 17 A in AC-3 and up to 40 A in AC-1, delivering about 7.5 kW (10 HP) at 460 VAC or 5 HP at 230 VAC, making it suitable for switching three-phase motors in industrial controls. The device features three normally open main contacts, a 24 V AC 50/60 Hz coil, and a contact rating for up to 460 VAC, with an ambient operating range of -25 to +60 C. Weighing roughly 0.75 lb (0.34 kg) and equipped with screw terminals, it is designed for DIN-rail mounting in compact control panels. The 3RT1025-1AC20 is part of Siemens' Sirius 3RT1 line and has a documented replacement in the 3RT2025-1AC20 series for future upgrades.