AC Under-Frequency
Description - The grid frequency is outside the permissible range. After grid resumes normal, wait 5 minutes (default duration) for automatic grid-connection.
Troubleshooting - Check the grid frequency and grid connections. If fault is caused by local conditions, ask the electricity provider to adjust the voltage at the feed-in point or to change the value of the monitored operational limits. If the grid frequency lies within the acceptable range and “F-fault” continues, please contact Sungrow.