Siemens · SINAMICS G120
This alarm indicates a defect occurring during the processing of Fail-safe I/O (F-IO). This suggests a problem with the safety-related input/output circuitry or its configuration, potentially compromising safety functions if not addressed.
Click steps to track your progress.
1. Measure the voltage at the terminals of the affected fail-safe input (e.g., X124/1 and X124/2 for F-DI) to confirm expected signal levels (e.g., 24VDC for ON, 0VDC for OFF).
2. Isolate the specific F-IO module or input by reviewing diagnostic messages or observing module LEDs to pinpoint the exact failing channel.
3. Verify the wiring integrity of the entire fail-safe circuit, checking for conductor breaks or insulation damage between the safety device and the F-IO module.
4. Compare the configured fail-safe parameters (e.g., P3090, P3105, P3120) with the actual wiring and safety circuit design documentation.
5. Perform a continuity test on the safety input cables (e.g., between terminal 1 and 2 for a two-channel input) with all power removed from the system.
6. Check the 24VDC auxiliary supply voltage at the F-IO module's power terminals (e.g., L+ and M) to ensure it is within specified limits (e.g., 22VDC-28VDC).