Rockwell Automation 9301 Series RSView32 Users Guide - Manual (Page 122)

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RSView32 User’s Guide
Setting up the evaluation interval
To set up the evaluation interval for the derived tag file:
1. On the menu bar, click Setup, and then click Derived Tag Setup.
2. In the Derived Tag Setup dialog box, type a brief description of the
derived tag file. This description is for your information only—it
does not appear anywhere else.
For example, if you were creating a derived tag file for a certain
area of your plant, you might type “West Wing Assembly Line” to
identify the area.
3. Choose a type of evaluation to specify how often to evaluate
expressions at runtime. When the evaluation interval expires,
RSView32 evaluates the expressions that contain tags with values
that have changed.
To have expressions evaluated as quickly as possible, click
Continuous. To have expressions evaluated at a particular interval,
click Periodic, and then type a number in the Evaluation Interval
field. You can use fractional seconds. For example, if you type .6,
the expression will be evaluated every six tenths of a second. Do
not specify an evaluation interval faster than the scan class
background period, DDE server polling rate, or OPC
® server
update rate.