Siemens SIRIUS 3RT2026-1AC24 Power Contactor — S0 Frame, Screw Terminals
The Siemens SIRIUS 3RT2026-1AC24 is a Size S0 power contactor in the SIRIUS family, designed for switching motor loads in industrial control panels. It mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 60715, with a 45 mm width that fits standard panel density. This is a 3-pole contactor with screw-type terminals on the magnet coil, rated for 3 hp at 230 V and carrying a typical mechanical service life of 10 million cycles. The AC-3 switching frequency maxes at 750 operations per hour, which is the standard motor-switching duty class — the number that governs real-world conveyor, pump, and fan cycling. It accepts solid or stranded conductors from 1 to 10 mm², and fine-stranded wire in dual configurations down to 0.5 mm². The main contact torque range is 16 to 8 Nm, so a calibrated driver is needed for consistent termination.
Mounting and Clearance
Mounting position is flexible: +/-180° rotation on a vertical surface, and tilt forward/backward by +/-22.5°. Required clearances around the contactor are 10 mm upwards, downwards, and forwards, and 6 mm at the side — tight enough for dense DIN-rail layouts but check side clearance if adjacent devices run hot. Operating temperature range is -25 to +60 °C, storage from -55 to +80 °C. The storage spec is the handling limit, not the running limit — don't let it sit in a hot warehouse above 80 °C, but the operating envelope covers most panel environments.
Switching Performance and Lifecycle
Mechanical life is typical at 10 million cycles. Electrical endurance depends on load: AC-1 (resistive) allows 1000 ops/h, AC-2 and AC-3 (motor start/run) allow 750 ops/h, and AC-4 (plugging/inching) drops to 250 ops/h. The arcing time sits at 10 ms, consistent with a contactor designed for clean break under inductive load.
Switching Capacity by Voltage
Rated switching capacity varies with coil voltage: 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. The 3 hp rating at 230 V is the motor nameplate figure — match the actual motor FLA, not just the hp number.