The Siemens 3RW4024-2TB05 is a SIRIUS soft starter in frame size S0, rated for 12.5 A at 40 °C, 11 A at 50 °C, and 10 A at 60 °C — the derating curve matters if your panel runs warm. Control supply is 24 V AC/DC at both 50 and 60 Hz, so one part covers both line frequencies without a jumper change.
The 12.5 A rating at 40 °C is the headline number, but the 10 A at 60 °C is the one that governs if your enclosure runs hot — derating starts above 40 °C. The integrated bypass contactor means this soft starter switches to line power after start, so the thyristors only handle the ramp-up thermal load; no external bypass contactor needed. Spring-loaded terminals on both the main current circuit and the auxiliary/control circuit accept 2x (0.25... 2.5 mm²) solid or stranded — no ring lugs required, which speeds panel wiring. The front clamping point accepts 1x 8 mm² or 2x (16... 10) AWG for the main conductors. Motor overload protection is built in, with adjustable current limitation and intrinsic device protection. The minimum load is 20 % of the rated current, so it won't regulate properly on a grossly oversized motor — size the soft starter to the motor FLA, not the other way. Pollution degree 3 per IEC 60947-4-2. Insulation voltage is 600 V.
Height is 150 mm, depth 155 mm. Clearance: 60 mm upwards, 40 mm downwards, 15 mm at the sides. Mounting position with an additional fan allows vertical surface mounting with +/-90° rotation and +/-22.5° tilt front/back; without a fan, only +/-10° rotation and +/-10° tilt. Maximum motor cable length is 300 m — fine for most motor centres; beyond that, check for voltage drop and reflected wave effects on the thyristors. The external reset input allows remote fault reset from a PLC or pushbutton.