SIRIUS 3RB2025-2PB0 — Solid-State Overload Relay in Current Production
This part carries ATEX approval (PTB 06 ATEX 3001 Ex II (2) GD), making it qualifiable and traceable for hazardous-area motor circuits in pharmaceutical GMP or chemical processing lines where documentation and change control are required. The IP20 front protection suits enclosed panel mounting.
Trip Class and Auxiliary Switching Capacity
The CLASS 20E trip curve means the relay allows a 20-second cold-start overload before tripping — sized for standard induction motor starts without nuisance trips, yet fast enough to protect windings under sustained overload. This is the spec that governs motor protection coordination in the panel. Auxiliary contact ratings are documented across multiple control voltages: 2 A at 24 V, 4 A at 120 V, 3 A at 230 V, and 0.55 A at 60 V. These cover the common signal levels for PLC inputs or contactor hold coils without intermediate relays. The relay withstands surge voltage of 6 kV and burst transients of 2 kV on power ports (severity 3 per IEC 61000-4-4), which keeps the motor control circuit compliant in industrial environments with switching transients from contactors and drives.
Mounting type is contactor mounting — the relay clips directly onto the matching SIRIUS contactor (e.g., 3RT series), saving DIN-rail space and reducing wiring between the overload and the contactor power terminals. No separate base or adapter required. Dimensions: 45 mm width, 73 mm height, 75 mm depth. The 45 mm width matches a standard 2.5-module DIN-rail footprint when mounted on the contactor. The 75 mm depth is the overall projection from the contactor face. Terminals accept solid conductors 0.5 to 4 mm² (2x 0.5 to 2.5 mm² for the main circuit), screw-type. AWG equivalents: 2x 14 to 10 for main contacts. No special crimp tools needed for the solid-wire range. Shock resistance is 15g for 11 ms — adequate for machine-mounted applications on conveyors or pumps.
The relay carries ATEX Ex II (2) GD certification (PTB 06 ATEX 3001), allowing installation in Zone 1/2 gas and Zone 21/22 dust atmospheres when paired with an appropriate contactor and enclosure. The 100 % relative humidity rating during operation confirms suitability for condensing environments. Pollution degree 3 rated at 690 V, which covers industrial environments with conductive pollution. Power dissipation at AC in hot operating state is 0.05 W total, 0.02 W per pole — negligible for panel thermal budgeting.