AI Over Frequency

What does F23 mean?

This Automatic Fault occurs due to an over-frequency anti-islanding condition, detected when the AC frequency exceeds qualification limits. The inverter stops selling power and disconnects from the grid to ensure safety and regulatory compliance.

• Utility grid frequency exceeding the configured upper limit (e.g., 60.5 Hz for a 60 Hz system) for anti-islanding detection.
• Inverter's internal frequency measurement circuit drift or calibration error.
• Nearby generator or grid disturbance causing transient frequency spikes.
• Misconfiguration of anti-islanding parameters (e.g., Parameter P4-05 for over-frequency threshold set too tight).
• Inverter attempting to operate in an unintentional islanded mode with a local load, leading to frequency instability.

Click steps to track your progress.

1. 1

   Measure utility grid frequency at the inverter's AC input terminals (L1, L2, L3) using a power quality analyzer to verify grid stability.

2. 2

   Verify anti-islanding frequency thresholds configured in the inverter (e.g., Parameter P4-05, P4-06) against local utility requirements.

3. 3

   Check all external grid connection points and switchgear for loose connections or arcing that could generate electrical noise affecting frequency measurement.

4. 4

   Perform an inverter self-test or calibration routine if available, to verify the accuracy of its internal frequency measurement circuit.

5. 5

   Temporarily disable anti-islanding protection (if allowed by local regulations and safe to do so for testing) to determine if the fault clears.