100651

Check PROFIBUS cable integrity

Inspect PROFIBUS DP cables for damage, proper shielding connection, and secure M12 connectors at NCU X101/X102 and drive terminals.

Ensure machine is in safe state before cable inspection

Verify PROFIBUS termination

Check 150-ohm terminating resistors are installed only at first and last PROFIBUS nodes. Remove any intermediate terminations.

Use PROFIBUS tester to measure line impedance - should read ~150 ohms

Check PROFIBUS addresses

Verify drive PROFIBUS addresses match HW Config settings. Check MD30100 $MA_PROFIBUS_ADR parameters correspond to physical drive addresses.

Use SIMATIC Manager to scan PROFIBUS network and compare with configured topology

Monitor PROFIBUS diagnostics

Access Diagnostics > Hardware > PROFIBUS DP in HMI to check bus load, error counters, and station status.

Bus load should be <50% for stable operation

Inspect DRIVE-CLiQ cables

Check all DRIVE-CLiQ cables for proper connection at NCU DRIVE-CLiQ ports and CU320 control units. Verify cable lengths within specifications.

Maximum DRIVE-CLiQ cable length is 100m total per line

Verify DRIVE-CLiQ topology

Use STARTER software to check configured vs. actual DRIVE-CLiQ topology. Ensure p0978 (DRIVE-CLiQ topology) matches physical wiring.

Topology changes require drive power cycle to take effect

Check EMI interference

Verify DRIVE-CLiQ cables are routed away from power cables and properly shielded. Check cabinet grounding and shield connections.

Minimum 200mm separation between DRIVE-CLiQ and power cables

Monitor DRIVE-CLiQ diagnostics

Access r2050 (DRIVE-CLiQ error) and r2052 (DRIVE-CLiQ component list) to identify failed components or communication errors.

Use STARTER trace function to monitor DRIVE-CLiQ communication quality

Check NCU LED indicators

Verify NCU PROFIBUS LEDs show proper status: RUN (green), ERROR (off). DRIVE-CLiQ LED should be steady green.

Red ERROR LED indicates hardware fault requiring NCU replacement

Perform NCU network test

Use Diagnostics > Service > Network test to verify NCU network interfaces. Check both PROFIBUS and DRIVE-CLiQ functionality.

Network test should complete without errors for healthy interfaces

Review NCU alarm buffer

Check alarm buffer for preceding hardware alarms (1xxxx series) that may indicate NCU network interface degradation.

Look for pattern of intermittent network alarms before permanent failure

Verify NCU firmware compatibility

Check NCU firmware version matches SIMODRIVE/SINAMICS firmware versions. Update if compatibility issues exist.

Always backup machine data before firmware updates

Check drive supply voltages

Measure 24VDC control voltage at drives. Should be 24V ±10%. Check for voltage drops during operation.

Use proper PPE when measuring voltages in live electrical panels

Verify drive status LEDs

Check SIMODRIVE 611D status LEDs: green=ready, red=fault. SINAMICS CU320 displays should show normal operation.

Flashing LEDs often indicate power supply instability

Monitor supply current consumption

Check 24VDC supply loading and current consumption. Verify supply capacity meets total drive requirements plus 20% margin.

Each SIMODRIVE 611D requires ~2A at 24VDC for control circuits