The Siemens 3RU2116-1HB1 is a SIRIUS thermal overload relay — the part that sits between a contactor and the motor to protect against sustained overcurrent. CLASS 10 trip class means it will open the circuit within 10 seconds at a locked-rotor condition, which is the standard match for standard induction motors starting across the line. Frame size S00 keeps it compact for grouped motor starters in a control panel.
Ratings and what they mean for fit
Rated motor power at 400 V is 3 kW, at 500 V it's 4 kW, and at 690 V it's 5.5 kW — so the same relay covers a band of motor sizes depending on your line voltage. The auxiliary contact set is integrated, not a bolt-on, and carries 2 A at 24 V, 3 A at 120 V, and 1 A at 400 V (AC). Those are the values a PLC input or contactor coil sees, so verify the load matches before wiring. Temperature compensation is rated from -40 to +60 °C, meaning the relay's thermal model stays accurate across that ambient range without manual derating. Operating ambient spans -40 to +70 °C; storage and transport go to -55 to +80 °C. That covers most indoor panel environments and unheated warehouses.
Mounting and wiring
Mounts stand-alone on a DIN rail or directly to the panel plate — any position is permitted. Screw terminals for the main circuit; wire range accepts 2x 0.5 to 1.5 mm² solid or stranded, or 2x 0.75 to 2.5 mm². The screwdriver tip is Pozidriv PZ2, shaft diameter 5 to 6 mm. Depth is 80 mm, width 45 mm, height 89 mm — fits alongside S00 contactors in a standard motor starter row.