Current rating and thermal derating
The 3RW4037-2TB04: The integrated bypass contact system means the thyristors are shorted out once the motor reaches full speed, eliminating the heat load from the semiconductor stack during continuous run — the derating curve applies to the start duty, not the steady-state.
Panel fit and wiring
Size S2 frame at 55 mm wide, 160 mm tall, 170 mm deep — fits a standard 55 mm-wide DIN-rail slot with screw and snap-on mounting. Clearance requirements: 60 mm upwards, 40 mm downwards, 30 mm at the side — the 30 mm side gap is the tightest; adjacent devices must respect that for airflow and wiring access.
Environmental and protection specs
Operates from -25 to +60 °C ambient, stores from -40 to +80 °C — the -25 °C floor covers cold-start conditions in unheated plant areas. Degree of pollution 3 per IEC 60947-4-2 — rated for conductive pollution typical in industrial control panels where condensation or light dust is present. Insulation voltage rated 600 V, operating frequency 50... 60 Hz — covers global 400 V and 480 V line supplies without derating.
Motor protection and control features
Built-in motor overload protection and intrinsic device protection — the soft starter monitors both the motor current and its own thyristor temperature, reducing the need for an external overload relay in many installations. Adjustable current limitation with a minimum load of 20 % — set the start current between 20 % and the full rated current of the unit, matching the motor's breakaway torque requirement without tripping upstream protection. External reset input allows remote fault clearing from a PLC or pushbutton station — the red fault display gives local indication.