The Siemens 3RT2023-1BB44 is a SIRIUS power contactor in Size S0, designed for switching motor loads in industrial control panels. It carries a 24 VDC coil and is fitted with screw-type terminals for main and auxiliary wiring. The contactor mounts on 35 mm DIN rail per DIN EN 60715, with screw-and-snap fastening, and allows ±180° rotation on a vertical surface plus ±22.5° tilt forward/backward — useful when panel layout demands a non-standard orientation.
Key ratings and what they mean for fit
The AC-3 switching frequency is rated at 1 000 operating cycles per hour maximum — that governs motor starting duty for pumps, fans, and conveyors. AC-4 duty (plugging/reversing) is limited to 300 cycles/h, so if your application involves frequent inching or reversing, factor that lower rate into the service life estimate. The mechanical life is 10 000 000 operations typical, which is the bearing/swing-arm endurance before replacement; electrical life under load will be lower and depends on the switching category and actual current. Wire termination accepts solid or stranded conductors from 1 to 10 mm² for the main circuit, and 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) for auxiliary circuits — covers standard panel wiring without needing ferrule adapters. The screw terminals are the standard S0 footprint, so replacement or retrofit into an existing S0 panel is straightforward. Dimensions: 85 mm high, 45 mm wide, 151 mm deep. The depth is the dimension that extends behind the DIN rail; at 151 mm it fits most standard 200 mm deep enclosures but may conflict with back-panel wiring troughs in shallow boxes. Clearance to adjacent devices: 10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm at the side — plan your DIN-rail spacing accordingly.