What It Is and Where It Fits
The Siemens 3RU2116-1BB0-ZW97 is a SIRIUS thermal overload relay in the Size S00 frame, designed for direct contactor mounting on the SIRIUS 3RT2 series. It provides Class 10 overload protection, meaning it will trip within 10 seconds at 7.2× the set current — the standard for standard-duty motor starting where the rotor is not locked for long. The relay uses a thermal bimetallic release, so it tracks the motor's true thermal state, not just a fixed curve. Size S00 is the smallest frame in the SIRIUS line, covering motor ratings roughly up to 7.5 kW at 400 V. It clips directly onto the contactor — no separate DIN-rail footprint needed — and the auxiliary switch is integrated into the housing, saving panel space.
Key Ratings — What They Mean for the Buyer
The relay is rated for a maximum operational voltage of 690 V, covering 400 V, 480 V, and 600 V class systems. At 24 V it switches 2 A; at 120 V it handles 3 A; at 230 V it's 2 A; and at 400 V it's 1 A. These are the auxiliary contact ratings for the trip-indicating circuit — the note "for message 'Tripped'" means this variant includes a remote signal contact that changes state when the relay trips, so a PLC or HMI can log the fault. Temperature compensation is active from -40 °C to +60 °C, so the trip curve stays accurate across most industrial environments. The relay itself operates from -40 °C to +70 °C and can be stored or transported from -55 °C to +80 °C. Mounting position is any orientation, which simplifies panel layout.
Compliance and Documentation
The relay carries a substance prohibitance date of 10/01/2009, indicating RoHS compliance per EU Directive 2002/95/EC. It is part of the SIRIUS family, which typically holds UL, CSA, and CE certifications — verify the specific approvals on the nameplate for your jurisdiction, but the platform is globally accepted.