22.4.4         Data Log Trends do not show any Data

Problem: Data Log Trends seem to not be collecting any history.


1. If you only configured a DATALOG group, but did not enable Data Logging for the Tags in your Trend Group, no data will be collected for the Trend Display.  You have to enable DATA LOGGING for each TAG using Tag Properties. 

2. You should also check that the Deadband for Data Logging is set appropriately. Too large of a Deadband will prevent any data from being logged. WebAccess collects each tags DATA in a separate file that allows remixing tags on a DATALOG trend without losing past data.

3. Change to Minute, Hour, Day and Second.  Verify if one of these are collecting Data.  If no Second Data, then verify that Disable Data Log Seconds recording and 3.2.23 Data Log Folder are set properly.