Line phase failure

What does F6.1 mean?

A missing line phase, periodically low DC link voltage, or inadequate line voltage quality has been detected in the incoming AC supply. This can lead to imbalanced motor operation, reduced torque, and potential damage to the inverter's input rectifier section if not addressed.

• Open circuit in one of the incoming AC line phases (L1, L2, L3) due to a blown fuse, tripped breaker, or loose connection.
• Severe voltage sag, undervoltage, or unbalance on the incoming AC mains supply, exceeding the drive's tolerance limits.
• Malfunctioning input rectifier bridge within the drive, preventing proper DC link charging from one or more phases.
• Incorrect phase sequence or phase rotation detected by the drive's input monitoring (if enabled, e.g., Parameter P0-11).
• Overloaded or undersized supply transformer leading to excessive voltage drop under load conditions.

Click steps to track your progress.

1. 1

   Disconnect power. Measure the incoming AC line voltage (L1-L2, L2-L3, L3-L1) at the drive's input terminals using a multimeter and verify phase balance.

2. 2

   Inspect all fuses and circuit breakers in the supply circuit upstream of the drive, checking for continuity and proper rating.

3. 3

   Check for tight connections at the drive's input terminals (L1, L2, L3) and throughout the supply wiring back to the main distribution panel.

4. 4

   Monitor the DC link voltage (e.g., Parameter P7-01) during operation to detect periodic drops or instability indicative of phase issues.

5. 5

   If applicable, check and adjust parameter P0-09 (Line voltage monitoring threshold) to ensure it's set correctly for the supply conditions.