Inside-delta topology and integrated bypass
The 3RW4457-6BC46: This unit supports inside-delta wiring, which lets you run the thyristors in the delta legs of a six-lead motor — that cuts the line current the soft starter handles by roughly 58 % compared to standard inline connection. The integrated bypass contact system takes the thyristors out of the circuit after start, so heat buildup in the enclosure during continuous run is from the bypass contacts, not the silicon.
Mounting, clearance, and termination
Mounting position is flexible: vertical surface with ±90° rotation, or ±22.5° tilt front-to-back. It needs 100 mm clearance above and 75 mm below for airflow, and only 5 mm at the sides — tight panel packing is possible if the vertical ducting is right. Power wiring options: stranded 70–240 mm², finely stranded 50–240 mm², or 2/0–500 kcmil for the main contacts.
Protection and diagnostics that save a service call
Built-in motor overload protection and intrinsic device protection mean you don't need a separate overload relay for most installations — the soft starter handles thermal modelling of the motor itself. Adjustable current limitation lets you set the start current profile to match the load, which is useful for conveyors or pumps that don't need full torque at zero speed. A display shows fault codes, and the unit accepts an external reset, so you can wire a remote reset button on the panel door rather than cycling main power. There's also a motor brake output integrated — handy for stopping a coasting load quickly without an external brake controller.