The Siemens SIRIUS 3RT2025-1AD04 is a size S0 power contactor with a 24 VDC magnet coil and screw-type terminals, designed for switching motor loads in industrial control panels. It mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, making it a direct fit for standard panel layouts. The contactor is rated for AC-3 switching up to 14 A at 480 V, which covers typical 3 hp motor loads at 230 V and 3 A at 400 V — the AC-3 rating is the one that governs real motor duty, not the higher AC-1 resistive figure.
Switching Capacity and Duty Ratings
The 3RT2025-1AD04 carries a 24 VDC coil rated at 6 A holding current. For DC switching on the main contacts, it handles 2 A at 48 V and 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, and 0.6 A at 440 V — these are the DC-1 resistive load ratings, not motor duty. The AC-3e maximum switching frequency is 1,000 operations per hour, matching the AC-1, AC-2, and AC-3 rates; AC-4 drops to 300 cycles per hour for plugging or inching duty. Mechanical service life is typical 10 million operations.
Mounting and Integration
Fastening method is screw and snap-on onto 35 mm DIN rail per DIN EN 60715. Mounting position allows +/-180° rotation on a vertical surface, plus +/-22.5° tilt forward and backward — useful when fitting into tight enclosures or angled subpanels. Clearance distances: 10 mm upwards, 10 mm forwards, 10 mm downwards, 6 mm at the side. Dimensions are 45 mm wide, 85 mm high, 141 mm deep — the depth matters when planning door clearance or back-panel depth behind a swing frame.
Wiring and Terminals
Main contacts use screw-type terminals accepting solid or stranded wire from 1 to 10 mm². For finer control wiring, two conductors per terminal are allowed: 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²). The magnet coil connection is also screw-type. No auxiliary switch is integrated — if aux contacts are needed, a separate side-mount block must be added.
Environmental and Operating Limits
Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C — the storage limit governs handling during shipping and off-season storage, not running conditions. Coil power consumption at 50 Hz is 0.25 A. Arcing time is 10 to 10 ms (a tight band typical of DC coil contactors). The contactor is rated for AC switching with a make/break time of 4 to 16 ms.