Rockwell Automation FactoryTalk View Machine Edition Users Guide - Manual (Page 372)

F ACTORY T ALK V IEW M ACHINE E DITION U SER ’ S G UIDE
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FactoryTalk View monitors the expression value rather than the original tag value. For
example, your machine might send values to the data source in the form of temperature in
degrees Celsius. You could use an expression to convert the value to degrees Fahrenheit,
and then monitor the expression result rather than the original tag value.
If you can assign an expression, a Browse button is present in the Exprn column in the
Connections tab.
To specify an expression, do one of the following
 In the “Tag / Expression” column, type the expression.
 In the Exprn column click the Browse button and then create an expression in the
Expression editor. Use this method if you want to check the expression syntax, or to
use multiple lines for the expression.
For more information about expressions, see Chapter 23.
Replace tags using tag substitution
You can replace tags assigned to the graphic objects in your display by using tag
substitution. You can also replace the tags used in expressions assigned to graphic objects.
For example, if you assign a tag called HoistHeight to multiple objects in the display, and
then decide to use the tag Hoist_height instead, you can use tag substitution to quickly
replace the old tag with the new tag.
You can replace:
 A tag name (with or without folder names).
 A folder name.
 The text in an expression.
 Tags contained in embedded variables.
To replace tags
1. Select one or more objects.
Type the expression here... ...or click the button to open the Expression editor..