What this contactor is and what it does
The Siemens SIRIUS 3RT2035-1NB30-0CC0 is a Size S2 power contactor with three normally-open main contacts, designed for switching motor loads and resistive loads in industrial control panels. It mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, so it fits standard enclosure backplates without adapters. The coil accepts 20-33 VDC and draws 2 VA at both 50 and 60 Hz, meaning a standard 24 VDC control supply from a PLC or relay drives it directly. At 24 VDC rated value it switches 10 A; at 48 VDC, 2 A; at 110 VDC, 1 A; and at 220 VDC, 0.3 A — these are the DC-13 switching capacities for the auxiliary contacts, so the buyer should match the load voltage to the right column.
Switching duty and mechanical endurance
The contactor is rated for different switching frequencies depending on the utilization category. For AC-1 (resistive loads) it handles up to 1200 operations per hour; for AC-3 (squirrel-cage motors, starting and disconnecting running) it manages 1000 ops/h; for AC-4 (inching, plugging, reversing) it drops to 300 ops/h. The AC-3e rating also sits at 1000 ops/h. Mechanical life is typical 10 million operations, so in a standard conveyor or pump application cycling a few times per hour, this contactor will outlast the panel. Arcing time runs 10-20 ms; operate time for both AC and DC coils is 30-55 ms, which is consistent for a Size S2 frame.
Mounting and clearances
The contactor measures 55 mm wide, 114 mm high, and 130 mm deep. For side-by-side mounting on DIN rail, allow 6 mm clearance at the side; upwards, forwards, and downwards each need 10 mm. The mounting position allows +/-180° rotation on a vertical surface and can be tilted forward/backward by +/-22.5°, so it fits in tight or angled enclosures. The coil uses screw-type terminals accepting 2x (0.5-1.5 mm²) or 2x (0.75-2.5 mm²) solid or stranded wire. An auxiliary switch is built in, which saves a separate auxiliary contact block for basic status feedback.