Solid-state overload relay for motor protection
The Siemens SIRIUS 3RB3026-1SB0-ZW96 is a solid-state overload relay in the S0 size, rated for a thermal current of 12 A and a maximum operating voltage of 690 V. The relay mounts directly onto a contactor, saving DIN-rail space in the panel.
Trip signaling and auxiliary contacts
This variant carries the note "for message tripped", meaning the integrated auxiliary switch is configured to signal a tripped state rather than a ready or energized state. The auxiliary switch is rated for switching at various control voltages: 2 A at 24 V, 4 A at 120 V, 3 A at 230 V, and 0.55 A at 60 V. That covers most PLC input and indicator lamp loads in a standard control panel. The shock resistance is 15g / 11 ms per IEC 60068-2-27, with the signaling contact in tripped position rated at 9g / 11 ms.
Main circuit terminals accept screw-type connections: solid wire 1x (0.5 to 4 mm²) or 2x (0.5 to 2.5 mm²), and stranded up to 2x 10 mm². The screwdriver spec calls for Pozidriv PZ2 tip with shaft diameter 5 to 6 mm. Main contact terminal screws are M4. The 45 mm width and 84 mm depth fit standard S0 contactor footprints.