Reversing starter, Size S0, 690 V AC-3
The Siemens 3RA2220-1KH24-0AP0 is a SIRIUS reversing starter in Size S0, rated for AC-3 duty up to 690 V. It ships as a complete assembly: the supplied contactor (3RT2024-2AP00) and link module (3RA2921-2AA00) are matched to the S0 frame, so the kit is complete — no separate ordering of interlock or busbar links. For high-inertia loads (fans, flywheels) that need a longer acceleration ramp, a Class 20 or 30 starter would be the correct choice.
Busbar snap-on and panel fit
Mounts by snapping directly onto 60 mm busbar systems — no DIN rail adapter needed. The fastening method is specified for vertical mounting only, with clearances: 50 mm upward, 32 mm forward, 10 mm downward, 10 mm at the side, and 0 mm backward. The 165 mm depth × 90 mm width × 260 mm height envelope fits standard S0 panel layouts. Main circuit connections use spring-loaded terminals — no screw torque to verify, no re-tightening on thermal cycling. This saves commissioning time on multi-starter panels and reduces the chance of a loose connection on a reversing pair.