What this contactor is and where it fits
The Siemens 3RT2025-1CK64-3MA0 is a SIRIUS power contactor in the Size S0 frame, designed for switching motor loads and resistive loads in control panels. It mounts via screw or snap-on onto 35 mm standard mounting rail per DIN EN 60715, with a 45 mm width that fits a standard DIN-rail slot. The coil is screw-type terminals, and the main contact wire range accepts solid or stranded 1 to 10 mm², with finer control wiring accommodated at 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²).
What the ratings mean for your circuit
The contactor is rated for 6 A at 24 V, 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, 3 A at 400 V, and 0.6 A at 440 V — these are the maximum continuous currents it can switch at those voltages. The AC-3 maximum switching frequency is 1 000 operations per hour, which is typical for motor starting duty; the AC-4 maximum drops to 300 operations per hour for inching or plugging duty where the contactor makes and breaks full load current. Mechanical life is rated at 10 000 000 operations typical, so the contactor itself will outlast most panel refreshes if the electrical load stays within ratings.
Panel integration notes
Mounting position allows +/-180° rotation on a vertical surface, and can be tilted forward or backward by +/-22.5°. Clearances: 10 mm upwards, 10 mm forwards, 10 mm downwards, 6 mm at the side. Depth is 141 mm, height 85 mm. Operating temperature range is -25 to +60 °C; storage range is -55 to +80 °C. The screw-type terminals accept the wire sizes listed — no special tools beyond a screwdriver and a ferrule crimper for stranded wire.