The Siemens 3RA2423-8XF32-2BB4 is a SIRIUS star-delta (wye-delta) contactor assembly — a pre-configured set of three contactors and a resistor-start (RS) kit, factory-assembled on a common mounting plate, for reduced-voltage starting of three-phase motors. It ships with three 3RT2024-2BB40 contactors and the 3RA2923-2BB2 RS assembly kit, so you get the complete switching group in one order code rather than sourcing and wiring individual components. Rated at 11 kW at 400 V (AC-3 motor duty), it also carries 15.6 kW at 500 V and 19 kW at 690 V — the 400 V figure is the one that governs most European panel designs.
The S0 contactor frame size keeps the footprint compact: 135 mm wide, 114 mm tall, 181 mm deep. Clearance requirements: 6 mm upwards, forwards, downwards, and to the side; zero clearance needed at the back — so you can push it flush against the backplane.
Coil, wiring, and environmental limits
The magnet coil is 24 VDC, with a closing power of 13.8 W and the same holding power — a continuous-duty coil that stays energized during the run state, typical for star-delta circuits where the main contactor holds in. Main circuit connections use spring-loaded terminals (cage clamp), accepting 2x (1 to 10 mm²) solid or 2x (0.5 to 2.5 mm²) stranded; auxiliary and control circuits also use spring-loaded terminals. No screw-torque checks needed — consistent clamping force over time. Vibration resistance: 11.8 g at 5 ms and 7.4 g at 10 ms (AC), 15 g at 5 ms and 10 g at 10 ms (DC) — robust for machine-mounted applications.
No official successor has been published; the assembly is the current generation. For BOM freeze or second-source planning, the three 3RT2024-2BB40 contactors inside are individually available, but the factory-assembled kit is the intended replacement unit.