#14 - SCADA Ignition Historical deadband

To avoid unnecessary overload of the amount of records of a Tag in the database, it is possible to edit the Historical Deadband, according to the process. In this example we are logging 6 Tags, coming from 6 sensors (3 temperature, 3 humidity).

• First we check the  tagid  that interests us in the MySQL database, in this case from 1 to 2.
  
  SELECT * FROM test.sqlth_te;

• We open Tools> DB Query Browser in Ignition and activate Auto-Refresh

• Data logging is being done with the default parameters that can be edited in the Tag properties:
  Sensor 1
     > Humidity OPC (Edit tag)
        History: Historical Deadband 0.01

By changing the default value from 0.01 to 10 of Humidity Sensor 1, just to illustrate the difference in the example, we note that there is a significant reduction in the volume of data entered in the database, however the granularity is lost as expected. The tip is to find the highest ideal Historical deadband value for your process and application in order to avoid inserting too much data in the DB.