Motor ratings that govern the fit
The 3RA2125-1KA24-0AP6: At 460/480 V it is rated 7.5 hp; at 575/600 V it delivers 10 hp — the voltage-dependent power ratings let you match the starter to the motor nameplate without oversizing. That is the standard protection for standard-start induction motors — fast enough to protect the winding during a stall, slow enough to ride through the starting inrush on a normal start. The degree of pollution 3 rating means it is suitable for industrial environments where conductive dust or occasional condensation is present — typical for a motor control centre (MCC) or a standalone panel on the plant floor.
Panel fit and mounting — what the dimensions actually tell you
Width is 45 mm — that is a single S0-size module on the DIN rail. Height is 193.1 mm and depth is 97.1 mm, so it projects about 100 mm from the rail. The S0 frame size is the mid-range in the SIRIUS feeder family; it sits between the compact S00 and the larger S2/S3 frames that handle higher currents. Snap-mounted to DIN rail or screw-mounted with an additional push-in lug — the mounting position is vertical only. Clearance distances are specified: 30 mm upwards, 10 mm forwards, 10 mm downwards, 9 mm at the side, and 0 mm backwards. That backwards-zero figure means the back of the housing can sit flush against the panel backplate, which simplifies layout in a tight enclosure. The supplied contactor is a 3RT2024-1AP60 and the supplied link module is a 3RA2921-1AA00 — these are the matched components that make this a coordinated starter assembly, not a random contactor-and-relay pair. The main contact wiring accepts stranded conductors from 1 to 10 mm², or two conductors of 2.5 to 6 mm² each.
Environmental limits for storage and operation
Operating temperature range is -20 to +60 °C; storage range is -50 to +80 °C; transport range is -55 to +80 °C. The -20 °C floor means it can sit in an unheated plant over a weekend shutdown and still start clean on Monday morning — no auxiliary heater required for most climates. Control supply voltage is 176 to 242 V at 50 Hz and 192 to 264 V at 60 Hz — that covers the standard 208-240 V control transformer taps used across North American and European panels. The coil draws from the same control bus as the PLC output, so no separate control power supply is needed.