237-3801

Check FS Cable Routing

Inspect FS communication cables for proper separation from power cables. Maintain minimum 10cm distance from motor power lines.

Power down system before cable inspection to prevent electrical hazards.

Verify Cable Integrity

Check FS communication cables for damage, proper shielding connection, and secure connector engagement at both TNC and drive ends.

Use cable tester to verify continuity and impedance on FS communication lines.

Test Communication Quality

Access MOD function 'Communication Diagnostics' to monitor FS telegram error rates and signal quality parameters.

Error rates above 1% indicate cable or interference issues requiring immediate attention.

Reset FS Communication

Execute emergency stop, then restart system to reinitialize FS communication handshake between TNC and affected drive.

Ensure all safety circuits are properly functioning before restart.

Check Drive FS Parameters

Verify drive FS configuration matches TNC settings in machine parameter MP7500 (FS Enable) and MP7501 (FS Cycle Time).

FS cycle time must be identical on TNC and all connected drives for proper synchronization.

Monitor Drive Status

Use TNC diagnostic screen 'Servo Diagnostics' to check drive FS status and telegram counter values in real-time.

Compare 'Soll' (target) and 'Ist' (actual) values shown in alarm message to identify synchronization drift.

Check System Load

Monitor TNC CPU load in MOD function 'System Information'. High CPU usage (>80%) can cause FS communication timing issues.

Reduce NC program complexity or increase interpolation cycle time if CPU load is consistently high.

Verify FS Timing Parameters

Check machine parameter MP7501 (FS Cycle Time) is set correctly for your drive configuration, typically 4ms or 8ms.

Never change FS timing parameters without consulting drive manufacturer specifications.

Analyze Communication Statistics

Access 'Service' menu and review FS communication statistics for missed cycles or timing violations.

Document timing statistics before and after parameter changes for troubleshooting reference.

Isolate Affected Drive

Identify specific drive from alarm parameter %1, then temporarily disconnect FS communication to isolate the faulty unit.

System safety functions will be disabled for disconnected drive - implement alternative safety measures.

Test Drive FS Module

Use drive manufacturer's diagnostic software to test internal FS module functionality and communication circuits.

Document all diagnostic test results for warranty claims or technical support.

Replace FS Module

If diagnostics confirm FS module failure, replace the drive or FS communication card according to manufacturer procedures.

FS module replacement requires safety system re-commissioning and validation testing.