The Siemens SIRIUS 3RU2116-0KB0-ZX95 is a thermal overload relay in size S00, designed for direct mounting onto a contactor in motor control circuits. It provides Class 10 tripping, meaning it will disconnect the motor within 10 seconds at 7.2× the set current — the standard protection for standard induction motors starting under load, like pumps or conveyors on a paper machine.
Ratings and what they mean for fit
The auxiliary contact is rated 2 A at 24 V, 3 A at 120 V, and 2 A at 230 V, covering the common control voltages in North American and European panels. At 400 V the auxiliary contact is rated 1 A, and at 690 V it drops to 0.3 A — so if you're switching a higher-voltage PLC input or a remote indication lamp, verify the voltage and current fall within these curves. The relay carries a rated insulation voltage of 690 V and is temperature-compensated from -40 to +60 °C, so it stays accurate in a hot mill enclosure or a cold warehouse. Mounting is via the contactor's own footprint — no separate DIN-rail bracket needed. The relay snaps onto the contactor and connects the main circuit through screw terminals accepting 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid or stranded wire.