What It Is and Where It Fits
The Siemens SIRIUS 3RT1916-2GJ51 is a clip-on auxiliary switch designed for use with SIRIUS contactors and other switching devices in control panels. It provides additional contact sets for signaling or control logic, with an adjustable time delay of 1.5 to 30 seconds, making it suitable for star-delta starting circuits. Rated for a maximum of 3 A, with specific switching capacities of 1 A at 24 VDC, 0.2 A at 125 VDC, and 0.1 A at 250 VDC, this switch handles low-power control signals reliably. The 150 ms recovery time ensures it resets quickly between operations in sequential logic. Clip-on fastening to a DIN rail or directly onto the contactor body simplifies panel assembly. The switch can be mounted in any position, and its compact dimensions — 45 mm wide, 38 mm high, 75 mm deep — fit neatly into crowded enclosures.
Sourcing and Lifecycle
The SIRIUS brand carries standard compliance documentation (RoHS, REACH, UL, IEC) for the series. If your quality team needs specific declarations, those are part of the standard documentation package for this product line.
Integration Notes
Clip-on mounting means it snaps directly onto a SIRIUS contactor or onto a DIN rail without tools. The adjustable time delay (1.5–30 s) is set via a potentiometer on the front face — no software or programming needed. The switch supports star-delta circuits, so it's a natural fit for motor starting applications where timed transition between star and delta windings is required. Basic insulation and pollution degree 3 ratings mean it's suitable for standard industrial environments without special isolation measures. Operating temperature range is -25 to +60 °C, with storage and transport tolerance from -40 to +85 °C. The 24 VDC rated coil (with a pickup threshold of 0.85 and full-scale value of 1.1) ensures reliable operation on standard 24 V control supplies.