Siemens 3RT2027-1BB40 3-Phase AC Power Contactor

Siemens 3RT2027-1BB40 is a three-pole power contactor designed for AC-3e/AC-3 duty. It switches motor loads up to 32 A and handles up to 15 kW at 400 V, making it suitable for start/stop control of small to mid-size industrial motors. The coil is 24 V DC, allowing direct interfacing with common PLC output modules, and the unit includes a single auxiliary contact pair—1 normally open and 1 normally closed—for signaling the control circuit. Wiring uses screw terminals for secure connections, and the device is sized as S0, enabling compact installation in control panels. The compact S0 size and a net weight of approximately 0.611 kg support easy mounting alongside other Sirius 3RT components. This Siemens Sirius 3RT2027-1BB40 is part of the 3RT family of motor starters, designed to pair with overload relays and other accessories for integrated motor control. Typical applications include conveyors, pumps, fans, and machine tools where dependable AC-3 motor switching, plus status feedback via the auxiliary contact, is required in industrial automation environments.