Active production and thermal derating
The 3RW4447-2BC35: Current rating is temperature-dependent: 748 A at 40 °C, derating to 667 A at 50 °C, and further to 580 A at 60 °C. The derating temperature threshold is 40 °C — above that ambient, the continuous current capability drops linearly. For a panel builder sizing the soft starter against a motor FLA, use the 40 °C figure as the base and apply the derating if the enclosure ambient runs hotter.
System voltage and environmental rating
Insulation voltage is rated 690 V, and the operating frequency covers 50 to 60 Hz. This matches standard European and North American line voltages up to 690 V phase-to-phase. The pollution degree is 3 per IEC 60947-4-2, meaning the device is designed for conductive pollution or dry non-conductive pollution that becomes conductive due to condensation — typical in industrial control panels without climate control. The soft starter includes integral motor overload protection and intrinsic device protection, which reduces the need for a separate overload relay in the motor branch circuit. Adjustable current limitation is also built in, allowing the starting current to be tuned to the load without external hardware.
Panel integration and termination
Mounting is screw fixing with a vertical mounting surface that allows +/-90° rotation and +/-22.5° tilt front-to-back. The envelope is 298 mm deep, 210 mm wide, and 230 mm high — confirm the enclosure depth accommodates the 298 mm plus clearance: 100 mm upwards, 75 mm downwards, and 5 mm at the side for ventilation. Main circuit termination accepts stranded 70...240 mm² or finely stranded 50...240 mm², with busbar connection as the listed method. For North American wire sizes, the clamping points accept 2/0 to 500 kcmil using both points, or 250...500 kcmil at the back point, and 3/0...600 kcmil at the front.
Inside-delta wiring and thyristor control
The 3RW4447-2BC35 supports inside-delta circuit configuration, which connects the soft starter's thyristors in the delta legs of a six-wire motor. This reduces the line current drawn through the soft starter to approximately 58% of the motor FLA, allowing a smaller-rated unit to control a larger motor. The thyristors are confirmed present — this is a standard silicon-controlled rectifier (SCR) design, not a hybrid or contactor-based soft starter. Minimum load is 8% of the rated current, meaning the soft starter can regulate down to that level without dropping out. The maximum motor cable length is 500 m — relevant for remote motor installations where long cable runs add capacitance and may cause nuisance tripping or ringing on the output.