Trip class and what it means on the line
The 3RU2116-4AB0-ZX95: If you're guarding a high-inertia load that needs a longer acceleration ramp, CLASS 10 may trip before the motor is up to speed; you'd step up to CLASS 20 or CLASS 30.
Size S00 — panel fit and mounting
It mounts directly onto the contactor via the fastening method listed as 'contactor mounting', so no separate DIN-rail clip or bracket is needed.
Auxiliary contact note — 'Tripped' message
The relay carries a note: 'for message Tripped'. That means the integrated auxiliary switch is wired to signal a trip condition — not just a standard NO/NC status, but a dedicated 'tripped' indication. On the line, that lets the PLC or HMI display a specific fault message rather than a generic 'overload' alarm, which speeds up troubleshooting.