Grid reconnection conditions not met

After a grid fault the inverter stays off the grid because the measured grid frequency or voltage is outside the allowed range for reconnection. Some country standards use tighter limits for reconnection than for normal operation, for example an upper reconnection frequency of 50.05 Hz under VDE AR-N 4105, and the most common cause is a frequency that is too high. The inverter itself is not faulty and switches back on by itself once frequency and voltage have stayed inside the range for the grid monitoring time. First, read out the live grid frequency and voltage, the country standard and the reconnection limits over the communication interface, then compare them with your own grid measurement. A voltage reading taken after the trip may look normal, because grid voltage at the inverter drops as soon as feed-in stops. Look for large local loads such as machines that make the grid fluctuate. If the grid itself is out of range, the grid operator decides on fixes or on allowing changed inverter settings. In rare cases the cause is an incorrect or edited country data set (grid code misconfiguration). Reloading the original data set for the installation country fixes this.

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• sentence 3: support check: partial - The inverter not being faulty and automatic switch-on after the grid monitoring time once values are in range are stated, but 'stayed inside for the monitoring time' is only loosely implied.
• sentence 4: support check: partial - Reading out frequency, voltage, country standard and limits via communication and using grid measurements to determine too high/low is stated, but the explicit 'compare with your own grid measurement' and the 'first' ordering are not. -->