Pre-assembled SIRIUS starter for motor branch circuits
The Siemens 3RA2125-1KD24-0AK6 is a SIRIUS non-fused direct motor starter, size S0, combining a 3RT2024-1AK60 contactor and a thermal bimetallic overload relay in one assembly.
Mounting and panel fit — 60 mm busbar snap-on
Snaps directly onto 60 mm busbar systems in vertical mounting position; the 45 mm width and 155 mm depth fit standard S0 feeder compartments, with 30 mm clearance upward and 10 mm forward for wiring access. Main contact wire range accepts 1–10 mm² stranded (2× 2.5–6 mm²), and the supplied link module 3RA2921-1AA00 connects the contactor to the overload block without additional busbars.
Power ratings across common supply voltages
At 400 V three-phase, the starter delivers 5.5 kW (11 A at 480 V, 11 A at 600 V); at 230 V single-phase it is rated 2 hp, and at 575/600 V three-phase it reaches 10 hp. Coil control voltage is 88–121 V at 50 Hz and 96–132 V at 60 Hz, covering standard 110–120 V control circuits with a 50/60 Hz tolerance band.