Active production, direct-fit for SIRIUS contactors
The 3RU2126-1GB0-ZX95 is a current-production SIRIUS thermal overload relay. It mounts directly onto the matching SIRIUS contactor via the contactor-mounting fastening method — no DIN rail adapter needed, no separate base. The S0 frame size means it mates with the S0 contactor footprint; if your panel was built around a different SIRIUS frame (S00, S2, S3), this relay will not physically lock on. This is the standard class for standard-start induction motors (pumps, fans, compressors) where the start time is under 10 seconds. If your motor has a longer acceleration ramp (high-inertia loads like centrifuges or crushers), a Class 20 or Class 30 relay is needed to avoid nuisance tripping during start.
Auxiliary contact ratings and wiring
The integrated auxiliary switch provides a changeover contact (NC + NO) for the trip signal. The contact ratings vary significantly by voltage: at 24 V it switches 2 A, at 120 V it switches 3 A, at 230 V it drops to 2 A, and at 400 V it is rated 1 A. The DC ratings are lower: 0.3 A at 60 V, 0.22 A at 110 V and 125 V, and 0.11 A at 220 V. The main contact screws are M4. The note on the listing reads 'for message Tripped' — this likely refers to the auxiliary contact function that signals the tripped state, not a separate alarm contact.
Voltage, power, and temperature envelope
At 480 V and 600 V the current rating is 6.3 A. The thermal power dissipation per pole is 2.2 W. Temperature compensation is active from -40 to +60 °C — above 60 °C ambient the relay may not accurately track the motor's thermal state. The MTTF with high demand rate is 2,280 years, which is typical for a passive electromechanical device with no moving parts in the sensing element.
Compliance and substance restrictions
The substance prohibition date is listed as 10/01/2009 — this is the RoHS compliance effective date (RoHS 2 / 2011/65/EU). The relay is designed with a thermal overload release using a bimetal strip, not electronic sensing. The dimensions are 85 mm depth, 45 mm width, and 85 mm height. Mounting position is any.