What this reversing starter packs
The Siemens 3RA2225-0KD23-0AK6 is a SIRIUS non-fused reversing motor starter in the S0 load feeder size — a factory-assembled combination of a reversing contactor pair, a thermal bimetallic overload relay, and a link module, all pre-wired and tested. It is designed to snap directly onto 60 mm busbar systems, saving panel space and wiring time compared to building the same reversing circuit from discrete components. The reversing contactor pair (supplied as 3RT2023-1AK60) handles direction reversal for three-phase motors up to 690 V AC-3, while the thermal overload (Class 10 trip class) protects against sustained overcurrents.
At 400 V, this starter is rated for 370 W motor output; at 500 V it handles 550 W, and at 690 V it reaches 750 W. These are the AC-3 motor switching ratings — the current values at 480 V (1.19 A) and 600 V (1.25 A) confirm it is sized for small reversing drives like conveyor reversers, actuator valves, or pump direction changes.
Mounting is vertical only, with the unit snapping onto 60 mm busbar systems via the supplied busbar adapter (8US1251-5NT10). The S0 size (155 mm deep × 90 mm wide × 260 mm high) means it occupies a standard feeder slot in a SIRIUS modular system. The supplied link module (3RA2921-1AA00) handles the mechanical and electrical interlocking between the two contactors, preventing both from closing simultaneously.