Analysis: Grid frequency too high
1. Check what the displayed AC frequency value is, check if the value is in the rated range.
2. Use a multimeter to check if the grid connection is correct ; and check if the grid frequency is too high
3. Check if the inverter’s safety code be set correctly and Grid over-frequency protection point be set to match actual situation.
4. Please Wait for a while until the grid frequency recovered, then check if the inverter can return to normal