The Siemens 3RU2116-0DB0 is a SIRIUS thermal overload relay, size S00, designed to protect motors against overload and phase failure by monitoring the motor current and tripping the associated contactor when the current exceeds the set threshold for a time defined by its CLASS 10 trip characteristic.
Rated insulation voltage is 690 V, covering 400 V and 480 V systems with headroom, and the relay carries motor power ratings at those voltages: 0.09 kW at 400 V, 0.12 kW at 500 V, and 0.12 kW at 690 V. The auxiliary contact ratings span multiple control voltages: 2 A at 24 V, 3 A at 120 V, 2 A at 230 V, 1 A at 400 V, and 0.75 A at 690 V — these are the switching capacities for the signal circuit, not the motor circuit. Temperature compensation is active from -40 °C to +60 °C, meaning the trip curve stays accurate across that ambient range without manual adjustment.
The S00 frame size (76 mm high, 45 mm wide, 70 mm deep) is the smallest SIRIUS overload relay footprint, designed to snap onto the matching S00 contactor (e.g., 3RT6015 or 3RT6017 series) without additional wiring between the relay and contactor — the power connections pass through the relay. Terminals accept 2× (0.5 to 1.5 mm²) or 2× (0.75 to 2.5 mm²) solid or stranded wire; screwdriver tip is Pozidriv PZ2 with a 5 to 6 mm shaft diameter.
Substance prohibitance per the manufacturer's declaration dates to 10/01/2009, indicating RoHS compliance for that cutoff.