542 A at 40 °C — what that means for the motor line
The 3RW4445-2BC36: For a 400 V motor pulling 500 A full-load, this unit has headroom at 40 °C but needs a panel fan or derating if the cabinet runs hotter. It supports inside-delta wiring, which reduces the line current by 58% compared to standard in-line connection — useful for large motors where the contactor and cabling cost matters. The adjustable current limitation lets you set the starting torque profile from 8% to 100% of the motor's locked-rotor current, so you can tune the ramp for a loaded conveyor or a high-inertia fan without oversizing the starter.
Panel fit and wiring — the dimensions that decide the cabinet
At 298 mm deep, 210 mm wide, and 230 mm tall, this starter needs a cabinet depth of at least 350 mm to leave room for the busbar connections and the 70–240 mm² stranded cable on the main terminals. The screw-fixing method means you bolt it to a backplate — no DIN rail adapter for this frame size. The mounting position allows ±90° rotation and ±22.5° tilt front/back, so you can orient it for busbar routing in a tight panel. Keep 100 mm clearance above and 75 mm below for airflow and cable bending radius — the thyristor heat sink relies on natural convection, not a fan.