What this star-delta assembly delivers
The 3RA2444-8XF32-1AG2 is a pre-assembled SIRIUS contactor set for star-delta (wye-delta) motor starting — a common method to reduce inrush current on larger three-phase motors during startup. It includes three contactors: two 3RT2045-1AG20 units for the line and delta legs, and one 3RT2035-1AG20 for the star leg. The operating frequency in AC-3 duty is 1,000 operations per hour maximum — the mechanical life of the contactors is 10,000,000 cycles typical, meaning the switching rate, not wear, sets the duty cycle limit in most applications.
Panel fit and mounting constraints
The assembly occupies 220 mm width, 180 mm height, and 244 mm depth — confirm the enclosure depth and side clearance before laying out the panel. Mounting position is flexible: the unit can be rotated ±180° on a vertical surface and tilted forward or backward by ±22.5°. Clearances around the assembly: 10 mm upwards, 10 mm forwards, 10 mm downwards, 10 mm to the side, and 0 mm backwards — the back face sits flush against the mounting surface. The magnet coil and auxiliary contacts also use screw terminals — no spring-cage option on this variant.
Thermal environment and protection coordination
The assembly is rated for vibration: 10.6 g at 5 ms and 6.3 g at 10 ms under AC conditions — check the mounting rail rigidity if the panel is on a machine subject to shock loads. The required upstream fuse rating for type 2 coordination is 160 A, using gG NH 3NA, DIAZED 5SB, or NEOZED 5SE fuses. This must be reflected in the panel schedule — the fuse clears a bolted fault before the contactor welds. The included RS assembly kit is 3RA2943-2C — this is the wiring and mechanical link between the three contactors. If the kit is damaged or missing, the assembly cannot be field-repaired without the specific Siemens kit.
Lifecycle and sourcing posture
This is a BOM-specified assembly; the three contactors and the RS kit are factory-matched. Substituting individual contactors from a different batch or manufacturer voids the coordination and the type-2 protection rating.