Star-delta contactor assembly for the commissioning window
The 3RA2423-8XH32-1BB4 is a Siemens SIRIUS pre-assembled star-delta contactor set, built around three 3RT2024 contactors and an RS assembly kit 3RA2923-2BB1 — one unit that hits the panel install date without wiring up individual contactors and interlocks. The magnet coil draws 13.8 W closing and holding at 24 VDC — the holding power is the same as the closing power, so the control transformer and DC supply must be sized for continuous 13.8 W per starter.
Mounting and integration into the panel
Snap-on mounting onto 35 mm standard DIN rail plus screw fixing — the S0 frame size (135 mm wide, 101 mm high, 181 mm deep) fits standard motor starter cubicles. Clearance requirements: 6 mm upwards, forwards, downwards, and to the side; 0 mm backwards — the back can sit flush against the panel backplate.
Termination and upstream protection
Required upstream fuse protection: gG NH 3NA, DIAZED 5SB, or NEOZED 5SE rated 25 A — this is the coordination spec for the star-delta transition; don't oversize the fuse or the contactor loses fault clearance.
No stock-holding claim — sourced per project requirement.