Star-delta contactor assembly, 75 kW at 400 V
The Siemens 3RA2445-8XH32-1NB3 is a factory-assembled SIRIUS contactor assembly for star-delta (wye-delta) motor starting, Size S3. It ships with three pre-configured contactors: two 3RT2045-1NB30-0CC0 units and one 3RT2036-1NB30, plus the RS assembly kit 3RA2943-2C. Rated 75 kW at 400 V AC-3 and 110 kW at 690 V AC-3, this assembly handles the transition from star to delta without external interlocking — the contactors are mechanically and electrically interlocked within the kit. The surge suppressor is built in with a varistor.
Mounting and panel fit — 244 mm deep, 220 mm wide
The footprint is 244 mm deep by 220 mm wide by 180 mm tall. Clearance requirements: 10 mm upwards, forwards, downwards, and to the side; 0 mm backwards.
Lifecycle and sourcing — current stage, quoted to order
The assembly requires external fusing: gG NH 3NA, DIAZED 5SB, or NEOZED 5SE rated 160 A per assignment type 2. The coil closing power at DC is 154 W.