Trend-Logging

Trendlog objects are used to log values from a single source, Trendlog Multiple objects provide multiple channels (but are rarely used).

Logging can be based on cyclic polling, COV (Tlog only) or triggered data acquisition (Trigger).

In addition to the values of the referenced object property, other events are also recorded (e.g. activation/deactivation of recording, emptying the buffer, etc.).

The size of the log buffer is determined by the BUFFER_SIZE property.

Record_Count provides information about the current utilization of the log buffer. Writing a null value to Record_Count clears the buffer.

Trendlog objects can be combined with event creation. In this case, a Notification_Threshold can be specified to notify clients to retrieve the values before logging ends or older values are overwritten.