Current rating and thermal derating — what the numbers mean for your motor
The 3RW4466-6BC45 is rated 2103 A at 40 °C ambient. That current drops to 1864 A at 50 °C and 1680 A at 60 °C. If your panel ambient runs above 40 °C, the motor full-load current must stay under the derated figure — the thyristor junction temperature is the limit, not the nameplate. The operating frequency is 50/60 Hz, so it works on either line frequency without derating.
Panel fit — dimensions, cable terminations, and mounting
The unit measures 780 mm high by 575 mm wide by 292 mm deep. That is a substantial footprint — plan the gland plate and busbar routing before the panel layout is frozen. Mounting is screw fixing, not DIN rail; the mounting position allows vertical surface with +/-90° rotation and +/-22.5° tilt forward/back. Main circuit cable termination accepts stranded 70–240 mm² and finely stranded 50–240 mm², plus AWG 2/0–500 kcmil. The main current circuit uses busbar connection; auxiliary and control circuits use screw-type terminals.
Integrated protection and bypass — what is built in and what you still need
Motor overload protection, intrinsic device protection, and adjustable current limitation are all onboard. The integrated bypass contactor means the thyristors are shorted out after start — no continuous heat sink loss, which is why the enclosure can be smaller than a full SCR stack. Minimum load is 8 %, so it handles lightly loaded motors without dropping out. The inside-delta circuit capability allows the soft starter to be wired in the motor delta loop, reducing the current through each thyristor leg to 58 % of line current — useful for retrofitting into existing delta-wound motors without re-cabling the main power path.