Access from the Insert Scan - Scan Criteria dialog and select Indicator from the Field drop-down list.TradeStation Help
The Select Indicator dialog is available in the final dialog as you create a new scan. TradeStation includes many indicators, or you can also build your own. You can select one or more indicators that you want to use as the criteria for your scan.
Access from the Insert Scan - Scan Criteria dialog and select Indicator from the Field drop-down list.
Name/Short Name/Modified 
Contains the indicators that are available to insert into the scan. For easier access, the Name, Short Name and Modified columns can be sorted.
Click OK. The indicator is added to the Insert Scan - Scan Criteria Field box. Or, click Cancel to exit the dialog without changes.