Technical data

Testing with the Variable Table
20.6 Monitoring Variables
Programming with STEP 7
Manual, 05/2010, A5E02789666-01 457
20.6 Monitoring Variables
20.6.1 Introduction to Monitoring Variables
The following methods are available to you for monitoring variables:
• Activate the Monitor function with the menu command Variable > Monitor. The values of the
selected variables are displayed in the variable table in accordance with the trigger point and
trigger frequency set. If you set the trigger frequency "Every cycle", you can toggle the Monitor
function off again with the menu command Variable > Monitor.
• You can update the values of the selected variables once and immediately using the menu
command Variable > Update Monitor Values. The current values of the selected variables are
displayed in the variable table.
Aborting "Monitoring" with ESC
If you press ESC while the "Monitoring" function is active, the function is terminated without a
query.
20.6.2 Defining the Trigger for Monitoring Variables
You can display on the programming device the current values of individual variables in a user
program at a specific point during program processing (trigger point) in order to monitor them.
When you select a trigger point you determine the point in time at which the monitor values of
variables will be displayed.
You can set the trigger point and a trigger frequency using the menu command Variable > Trigger.
Trigger Possible Settings
Trigger point Start of cycle
End of cycle
Transition from RUN to STOP
Trigger frequency Once
Every cycle