37 kW at 400 V — what the star-delta assembly includes
The Siemens 3RA2435-8XE32-1NB3 is a SIRIUS contactor assembly purpose-built for star-delta (wye-delta) motor starting. It ships as a pre-configured set: main contactor 3RT2035-1NB30-0CC0, star contactor 3RT2035-1NB30, and delta contactor 3RT2027-1BB40, plus the RS assembly kit 3RA2933-2C.
Panel fit and mounting constraints
Dimensions: 177.5 mm wide, 142 mm high, 223 mm deep. Required clearances: 10 mm upwards, downwards, and sideways; 0 mm backwards. The size S2 contactor frame determines the panel cutout and rail spacing.
Wiring and fuse assignment
Main circuit terminals accept 2x (1–35 mm²) solid or stranded, plus 1x (1–50 mm²). The coil is screw-type, rated at DC 20–33 V with 28 W closing power and 4 W holding power. For type 2 coordination, the required upstream fuses are gG NH 3NA, DIAZED 5SB, or NEOZED 5SE at 80 A. The assembly has 3 instantaneous auxiliary contacts and a mechanical life of 10,000,000 operations typical.