Capacitor switching contactor — SIRIUS size S0
The Siemens 3RT2628-1BF45 is a SIRIUS capacitor contactor in frame size S0, designed for switching capacitive loads in power factor correction banks. It is a DC-operated contactor with a screw-type coil terminal block. Rated for 6 A at 24 V DC and 3 A at 400 V AC, it handles capacitor inrush without welding or excessive arcing — the arcing time is held to 10 ms.
Switching ratings across voltage bands
At 230 V AC the contactor switches 6 A; at 400 V AC it switches 3 A; at 690 V AC it switches 1 A. The DC switching capability is 6 A at 24 V, 2 A at 60 V, 1 A at 110 V, 0.9 A at 125 V, and 0.3 A at 220 V. Maximum switching frequency at 230 V, 240 V, and 400 V is 100 operations per hour; at 480 V it drops to 70 1/h, at 500 V to 65 1/h, at 600 V to 45 1/h, and at 690 V to 36 1/h.
Mounting, wiring, and environment
Mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 50022. The mounting position allows ±180° rotation on a vertical surface and ±22.5° tilt forward/backward. Solid wire termination accepts 2x (0.5...1.5 mm²), 2x (0.75...2.5 mm²), or 2x 4 mm²; stranded wire accepts 2x (1...2.5 mm²) or 2x (2.5...10 mm²). Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C.