Reversing starter for 60 mm busbars — SIRIUS S0
The Siemens 3RA2220-1GH24-0BB4 is a SIRIUS reversing starter in size S0, designed to snap directly onto 60 mm busbar systems for panel builds where space on the DIN rail is tight. It combines a reversing contactor pair and overload relay in one assembly — spring-loaded terminals for the main circuit keep wiring fast. The 24 V DC coil matches common control-voltage rails in PLC cabinets.
The reversing starter includes the supplied contactor (3RT2024-2BB40) and link module (3RA2921-2AA00), so it arrives as a ready-to-wire unit. Vertical mounting position is required for proper heat dissipation — the 260 mm height and 90 mm width fit within a standard busbar compartment. Ambient operating range is -20 to +60 °C, with storage and transport limits from -50 to +80 °C. The S0 circuit-breaker size coordinates with the starter for selective short-circuit protection.
Lifecycle and sourcing — active, quoted to order
Mounts on 60 mm busbars with a 165 mm depth, leaving 50 mm clearance above and 32 mm forward for wiring access — no extra DIN-rail adapter needed.