352 A at 40 °C — the derating curve drives the panel fit
The 3RW4443-6BC45: That 40 °C figure is the thermal anchor — if the enclosure ambient runs above that, the usable current drops by about 40 A per 10 °C rise. Plan the panel ventilation around the worst-case derated number, not the headline 352 A. Insulation voltage is rated 690 V with a 50/60 Hz operating frequency. Pollution degree 3 per IEC 60947-4-2 means it's certified for the conductive-dust and condensation environment typical of industrial motor control centres — not a clean-room part.
Inside-delta wiring — line current cut by 58%
The 3RW4443-6BC45 supports inside-delta circuit wiring, which connects the thyristors in series with each motor winding rather than the supply lines. This reduces the line current the soft starter must carry to roughly 58% of the motor FLA — so a 352 A unit can handle a motor drawing about 600 A line current when wired inside-delta. The thyristors themselves are present, and the unit includes adjustable current limitation for precise ramp control. Motor overload protection is built in, along with intrinsic device protection that monitors the thyristor junction temperature and trips before the silicon exceeds its SOA. An external reset input and a display for fault signals are standard — no separate overload relay needed for most installations.
Mounting and wiring — screw-fixed, busbar main circuit
Fastening is by screw fixing onto a vertical mounting surface, rotatable ±90° and tiltable ±22.5° front/back. Clearance requirements: 100 mm upwards, 75 mm downwards, 5 mm at the sides. The main current circuit uses busbar connection — stranded cable 70–240 mm², finely stranded 50–240 mm², or AWG 2/0–500 kcmil. Solid auxiliary wiring is 0.5–2.5 mm². Dimensions: 298 mm depth, 210 mm width, 230 mm height. The 298 mm depth is the critical dimension for enclosure depth — standard 300 mm deep panels will fit, but the gland plate and backplane clearance need to be checked against the busbar exit.
Active production — no obsolescence signal
Storage temperature range is -25 to +80 °C; during operation the ambient limit is 60 °C. The minimum load is 8% of rated current — below that the thyristor turn-off may not be reliable, so confirm the motor no-load current exceeds 28 A for the 352 A unit.