Panel fit and mounting — 192 x 170 x 270 mm
The 3RW4427-1BC45 measures 192 mm high, 170 mm wide, and 270 mm deep. It mounts via screw fixing and accepts a vertical mounting surface with ±90° rotation and ±22.5° tilt front-to-back. Clearance for airflow: 100 mm above, 75 mm below, 5 mm at the sides.
Termination and wiring — box terminals, dual conductors
Main circuit connections use box terminals accepting 2x (4 … 50 mm²) stranded or 2x (10 … 1/0 AWG) using both clamping points. The front and back clamping points each accept 10 … 2/0 AWG. Maximum motor cable length is 500 m.
Soft start topology — thyristor stack with integrated bypass
The 3RW4427-1BC45 uses thyristors for the soft-start ramp and an integrated bypass contact system that closes once the motor is at full speed. This bypass eliminates thyristor conduction losses during run, keeping the enclosure cooler and improving efficiency. It supports inside-delta circuit wiring, which reduces the current through each soft starter phase to 58% of the line current — useful for retrofitting into existing delta-wound motor circuits without upsizing the starter.
Protection and control — adjustable current limit, motor overload
Adjustable current limitation lets you set the start current between 8% and 100% of the rated motor current. The unit provides motor overload protection and intrinsic device protection. Fault signals are shown on an integrated display. An external reset input allows remote clearing of trip conditions without opening the panel door.
Environmental and electrical ratings
Insulation voltage rated at 690 V, pollution degree 3 per IEC 60947-4-2. Storage temperature range -25 … +80 °C; maximum ambient during operation is 60 °C. The derating temperature threshold is 40 °C.