You can create logic statements like IF, OR, or AND and create calculated tags.
To use IF/OR/AND logic begin by creating a Calculated Trend.
Give your Calculated Trend a name.
Click on the Sigma symbol at right (Σ).
Select the If function.
Create your If statement. In the example below we used three trends to establish our logic, InFlow, Storm_Mode, and Alarm_Output.
if([InFlow]>1500 && ([Storm_Mode]=1 || [Alarm_Output]=1), [InFlow], '!NODATA!')
reads.... If the tag InFlow is greater than 1500 and either the tag Storm_Mode or Alarm_Output are equal to 1, then draw the tag InFlow. If not, draw No Data
You use a double ampersand && for the AND statement and a double pipe or vertical bar || for the IF statement.
Use the syntax '!NODATA!' to represent a value of No Data.
The end result is below.