Frame size and mounting constraints
The 3RW3046-2BB14 is a Size S3 SIRIUS soft starter — the frame that carries the 80 A rating at 40 °C. Dimensions are 170 mm high, 70 mm wide, and 190 mm deep, which fits a standard 200 mm deep enclosure with room for the required clearances: 60 mm above, 40 mm below, and 30 mm at the sides for airflow and wiring access. Mounting is via screw fixing or snap-on onto a DIN rail, with the unit rotatable ±10° or tiltable ±10° front-to-back on a vertical surface — useful when fitting into an existing panel where the rail is not perfectly plumb.
Current rating and thermal reality
The derating temperature threshold is 40 °C, so any panel ambient above that means the motor full-load current must be checked against the lower figure — a 75 A motor at 50 °C is within range, but at 60 °C the 66 A limit bites. Minimum load is 10 % of the rated current — below that the soft starter may not fire the thyristors reliably. This matters for unloaded motor testing or very small motors on the same unit.
Wiring and termination
Main circuit power terminals are screw-type, accepting 2 x (10 … 70 mm²) stranded or 2 x (10 … 50 mm²) finely stranded wire. Both front and back clamping points on the main terminals accept 10 … 2/0 AWG, giving flexibility for landing incoming and outgoing cables on opposite sides. Maximum motor cable length is 300 m — beyond that, capacitive charging current from the cable can cause nuisance tripping or prevent the starter from turning off cleanly. Keep the run under that limit, or add an output reactor.
Control supply and environment
Control supply voltage is 110 … 230 VDC — a wide-range DC input that covers standard 125 VDC and 220 VDC control buses without a separate power supply. The unit operates on 50 or 60 Hz line frequency, so it is at home on either 50 Hz or 60 Hz networks without adjustment. Rated insulation voltage is 600 V, with pollution degree 3 per IEC 60947-4-2 — suitable for industrial environments where conductive dust or condensation is present.
No pin-compatible direct replacement exists within the SIRIUS family — the 3RW3046-2BB14 is the Size S3 variant at this current level. If a project needs a different frame size or current rating, the SIRIUS soft starter range offers other sizes, but they differ in footprint and terminal layout.