What this SIRIUS 3RA2 packs into a 45 mm footprint
The Siemens 3RA2120-1AA23-0AP6 is a non-fused motor starter from the SIRIUS 3RA2 family, size S0 — a direct starter that combines a contactor and a thermal bimetallic overload relay with a magnetic short-circuit trip in one 45 mm wide package. Rated for AC-3 duty up to 690 V, it delivers 550 W at 400 V (0.1 hp at 230 V, 0.75 hp at 460/480 V and 575/600 V) — sized for small motor loads like pumps, fans, and conveyors in a control panel. The starter ships with a 3RT2023-1AP60 contactor and a 3RA2921-1AA00 link module; the circuit-breaker section is size S00.
Mounting, clearances, and panel fit
Snap-mounted onto a DIN rail or screw-mounted with an additional push-in lug — mounting position is vertical only. Dimensions: 45 mm wide, 193.1 mm high, 97.1 mm deep. Required clearances: 30 mm upwards, 10 mm forwards, 10 mm downwards, 9 mm at the side, and 0 mm backwards — plan the enclosure depth and ventilation accordingly. Pollution degree 3 (industrial environment) and assignment type 2 coordination mean the starter handles typical panel contaminants and fault coordination with upstream devices.