<Cause>

The setting for [System Setting] -> [Alarm Server] -> [Data Output Setting] -> [Number of Data to Save] is small.

<Solution>

Increase the setting for [Number of Data to Save].
If the display mode of the alarm part is "alarm history" or "event history", each occurrence and each reset is counted as one data.
Consequently, to keep one error bit change as historical data, "2" should be set at minimum.