Heidenhain · TNC CNC Controllers
This error indicates a failure in the cross-comparison of SPLC-CC outputs. It occurs when the Safety PLC (SPLC) program of the CC[x] defines an output as 0 (LOW), but the value read from the terminal for that output is 1 (HIGH), suggesting a discrepancy between commanded and actual output states.
Click steps to track your progress.
Check the physical wiring of the faulty output (indicated by %4) for any short circuits, external voltage sources, or incorrect connections.
Review the SPLC program logic for the affected output to ensure signals for setting and resetting the output remain stable for a minimum of 2 SPLC cycles.
Verify the output module's functionality and its ability to correctly switch between LOW and HIGH states.
Measure the voltage at the output terminal to confirm the actual state when commanded LOW and HIGH by the SPLC.