The Logging_Type value specifies whether the trend log collects record periodically, by change of value, or via “triggered” acquisition.
The Log_Interval value specifies a periodic value, in hundredths of a second, that the referenced property is logged when the Logging_Type variable value is POLLED. The variable value shall be zero and ignored when the Logging_Type variable value is anything other than POLLED.
The Align_Intervals indicates whether clock-aligned periodic logging shall be enabled. When clock-aligned periodic logging is enabled, and the Log_Interval is a factor of a second, minute, hour, or day, then the beginning of the priod shall coincide with the next clock second, minute, hour, or day.
The Interval_Offset value indicates an offset in hundredths of seconds from the beginning of the specified logging period until logging shall actually begin. The offset shall be interpreted as the Interval_Offset modulo the Log_Interval. For example, if the Log_Interval is 30 and the Interval_Offset is 31, then the offset shall be 1.
When the Trigger variable value transitions from true to false and the Logging_Type is TRIGGERED then the trend log shall serialize the referenced property. The Trigger variable value is reset to false when data acquisition is completed.