How to
Enabling a Trend Log
You enable trend log to start recording values.
The interval trend log and change of value trend log start recording values when the configured activation conditions are met. If an activation variable is used, both the activation variable and the activation time have to be true for the trend log to start recording.
On all trend logs, you can stop recording values by disabling the trend log. To resume recording, you enable the trend log. For more information, see Disabling a Trend Log .
Activation Variable
You configure an activation variable to have the trend log start recording values when a connected variable goes on. This variable can be a scheduled variable or a variable from a switch.
You can also have the trend log stop recording when the variable, such as a fan, goes off. For example, you can use this feature to log the effective time a fan is on.
Start at activation time
You configure an activation time to have the trend log start recording values at a specified time.
For Interval Trend Logs, the logging interval is aligned with the activation time. For more information, see Interval Trend Logs .
In WorkStation, System Tree pane, select the folder or SmartStruxure server where the trend log is located.
Select the trend log you want to enable.
On the Actions menu, point to Activation, and then click Enable trend log .
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The trend log is now enabled and starts recording when its start condition is fulfilled.
Disabling a Trend Log
Trend Log Activation
Actions Menu – Activation Submenu
Trend Log Does Not Start Record Due to the Start Condition
Trend Chart Does Not Show Trend Log Series