What the 232 A rating means for your motor load
The Siemens 3RW4435-2BC36 SIRIUS soft starter is rated 232 A at 40 °C. The thyristors manage the starting surge during ramp-up. Derate to 203 A at 50 °C and 173 A at 60 °C if the panel ambient runs hot; the 40 °C derating temperature is the baseline, so above that the thyristor junction temperature climbs and the unit sheds capacity.
Inside-delta wiring — what it changes
The 3RW4435-2BC36 supports inside-delta circuit configuration, which drops the current through each soft starter phase to 58 % of the motor full-load current — a 232 A unit in inside-delta can control a motor drawing up to 400 A line current, effectively doubling the motor size the same frame can handle. Inside-delta wiring requires six motor leads (not the standard three) and changes the thyristor voltage stress — the 690 V insulation voltage rating covers the higher phase-to-phase voltage the thyristors see in this topology.
Screw fixing to a vertical mounting surface, rotatable ±90° and tiltable ±22.5° front-to-back — gives flexibility for tight enclosures but the 270 mm depth, 170 mm width, and 200 mm height need a backplate that clears the gland plate. Clearance requirements: 100 mm above, 75 mm below, 5 mm at the sides — the 5 mm side gap is tight; adjacent devices or busbars need that minimum to avoid heat buildup from the thyristor stack.
Wiring and connection notes
Main current circuit accepts busbar connection or cable: stranded 25–120 mm², finely stranded 16–95 mm², or solid 2x (0.25–1.5 mm²) for the auxiliary contacts. Maximum wire length to the motor is 500 m — beyond that, voltage drop and cable capacitance can cause nuisance tripping on the thyristor gate drive. Adjustable current limitation and motor overload protection are built in, with an external reset input and a display for fault signals — no separate overload relay needed for most applications.