Reversing contactor assembly for motor direction control
The Siemens 3RA2327-8XB30-2BB4 is a SIRIUS reversing contactor assembly, S0 frame size, designed for forward/reverse motor control in a single package. It ships with two 3RT2027-2BB40 contactors pre-assembled and mechanically interlocked, eliminating the need to source and wire separate contactors with a mechanical interlock kit. The AC-3 switching frequency is 750 operations per hour maximum, suitable for frequent jogging or inching applications on conveyors, hoists, and machine tool spindles. The coil is 24 V DC, spring-type terminals on the magnet coil side.
Mounting and panel integration constraints
The assembly occupies 90 mm width, 114 mm height, 107 mm depth — the S0 frame footprint is standard across the SIRIUS contactor family, so panel cutouts and gland-plate planning carry over from other S0 devices. Clearance requirements: 6 mm upwards, forwards, downwards, and to the side; 0 mm backwards (the DIN rail provides the rear clearance). Vibration resistance is 13.5 g / 5 ms and 8.3 g / 10 ms on AC, 15 g / 5 ms and 10 g / 10 ms on DC — this meets typical industrial panel vibration profiles per IEC 60068-2-6.
Lifecycle and sourcing posture
For audit purposes, the assembly carries the Siemens SIRIUS brand and is fully compliant with the IEC 60947-4-1 standard for contactors and motor starters.