AI L1L2 Over Voltage

What does F33 mean?

This fault indicates an L1-L2 over-voltage condition (260 V) detected by the anti-islanding protection, triggering a slow disconnect. This mechanism ensures the inverter disconnects from an unstable grid, protecting both the inverter and grid from potential damage due to excessive voltage.

• Grid L1-L2 phase-to-phase voltage exceeding 260 V for a sustained duration, pointing to persistent grid instability or an extended high voltage condition.
• Grid voltage imbalance or prolonged over-voltage between L1 and L2 due to power network configuration or reactive power issues.
• Inverter's internal L1-L2 voltage measurement hardware suffering from cumulative drift or partial component failure over time.
• Anti-islanding parameter P_AI_L1L2_Volt_Max_Slow configured too tightly, leading to nuisance trips on acceptable grid voltage variations.

Click steps to track your progress.

1. 1

   Using a true RMS multimeter, continuously monitor the L1-L2 phase-to-phase voltage at the inverter's input terminals over several hours to observe any sustained readings above 260 V.

2. 2

   Compare the measured L1-L2 voltage values against the inverter's configured anti-islanding slow trip threshold (e.g., P_AI_L1L2_Volt_Slow).

3. 3

   Verify the integrity of the main AC input cabling from the grid connection point to the inverter (e.g., for conductor size, termination quality).

4. 4

   Request a power quality survey from the utility provider or an electrical contractor to identify persistent over-voltage conditions on the L1-L2 phases.

5. 5

   If grid conditions are confirmed stable, consider adjusting the L1-L2 slow over-voltage parameter (e.g., P_AI_L1L2_Volt_Max_Slow) upwards slightly, if allowed by grid codes.