Wye-delta starter assembly — what ships inside
The 3RA2426-8XE32-1BB4 is a Siemens SIRIUS pre-assembled contactor set for star-delta (wye-delta) motor starting. It comes as a complete assembly with three contactors: 3RT2027-1BB40-0CC0, 3RT2027-1BB40, and 3RT2026-1BB40, plus the RS assembly kit 3RA2923-2BB1. The S0 contactor frame size keeps the assembly compact for a 135 mm width, 101 mm height, and 181 mm depth.
Mounting and panel fit
Clearance around the unit: 6 mm upwards, forwards, downwards, and to the side; 0 mm backwards. That zero rear gap means it can sit flush against the panel backplane without needing breathing space.
Termination and wiring
Main current circuit and auxiliary/control circuit both use screw-type terminals. AWG equivalents: 2x (16... 12) and 2x (14... 8). The magnet coil is also screw-terminal terminated, rated at 24 V DC with a closing and holding power of 13.8 W. No auxiliary switch or bus communication extension is fitted on this variant.
Environmental and shock ratings
Shock resistance: 13.5 g / 5 ms and 8.3 g / 10 ms on AC, 15 g / 5 ms and 10 g / 10 ms on DC — relevant if the panel is on a vibrating conveyor or mobile equipment. Mechanical life of the contactor typical is 10,000,000 operations — the wye-delta switching cycle counts as one start, so budget accordingly for high-duty applications.