Pre-assembled reversing pair — two 3RT2016-2BB42 contactors on a common base
The 3RA2316-8XB30-2BB4 is a Siemens SIRIUS reversing contactor assembly that ships as a factory-matched pair of 3RT2016-2BB42 contactors, mechanically interlocked and pre-wired for forward/reverse motor control. This saves panel-build time over sourcing and assembling two separate contactors plus a mechanical interlock bracket. The 24 V DC coil keeps the control circuit in the low-voltage safety zone — common on PLC-driven panels where 24 V is the standard I/O rail.
DIN rail footprint and wiring — S00 size with spring terminals
The assembly measures 90 mm wide by 84 mm tall by 83 mm deep — the S00 contactor frame size. It snaps onto 35 mm standard mounting rail (screw-fix also supported) and can be rotated +/-180° on a vertical surface or tilted +/-22.5° forward/backward, giving flexibility in tight enclosures. Both the main power circuit and the magnet coil use spring-loaded terminals — no screwdriver needed for the wire connection. Clearance around the unit: 6 mm upwards, forwards, downwards, and to the sides; 0 mm backwards allows flush mounting against the back panel.
Duty cycle and environmental limits
Switching rate maxes at 750 cycles per hour in AC-3 or AC-3e duty — enough for frequent start/stop reversing applications like conveyor shuttles or hoist traverses. Mechanical life is 10 million cycles typical, so the contactor outlasts most machine rebuild intervals. Rated for operation from -25 °C to +60 °C ambient — install it in an unheated panel shed or a washdown area without derating concerns. Storage range is -55 °C to +80 °C. Shock resistance tested at 10.5g for 5 ms and 6.6g for 10 ms, covering both AC and DC coil variants.