The Siemens 3RU2116-1BB0-ZW96 is a SIRIUS thermal overload relay, size S00, designed for direct contactor mounting onto Siemens 3RT2 contactors. This variant carries an integrated auxiliary switch with a dedicated trip-indication function — the note "for message 'Tripped'" means the N/C contact opens and the N/O contact closes only when the relay has actually tripped, not when it is simply reset or powered down.
Switching capacity and contact ratings
The auxiliary contacts are rated for switching at multiple common control voltages: 3 A at 120 V, 2 A at 24 V and 230 V, 1 A at 400 V, and 0.75 A at 690 V. At 60 V and 125 V the rating drops to 0.3 A and 0.22 A respectively, and at 220 V it is 0.11 A. These are the make/break capacities for the integrated auxiliary switch — not the main overload current setting, which is set via the adjustment dial on the relay body. The main circuit is rated for a maximum of 690 V, with corresponding motor power ratings: 0.75 kW at 400 V and 500 V, 1.1 kW at 690 V. At 480 V and 600 V the current rating is 2 A. The relay is temperature-compensated from -40 °C to +60 °C, so the trip curve stays consistent across a hot panel or a cold startup.
Fastening is via contactor mounting — the relay clips directly onto the front of a SIRIUS contactor, saving DIN rail space and reducing wiring between the contactor and overload. The main circuit uses screw-type terminals, accepting 2× (0.5 to 1.5 mm²) or 2× (0.75 to 2.5 mm²) solid or stranded wire. The M3 main contact screws are standard for this class.