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Specifying tag names where tag data is needed, Logging tag values, Observing tag-related limits – Rockwell Automation FactoryTalk View Site Edition Users Guide User Manual

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Specifying tag names where tag data is needed

Specify data server or HMI tag names in an application, wherever live tag data is needed.

For example, you could create a graphic object that represents a vat on a production line,
and then set up the object to show the level of the vat at run time.

To do this, attach Fill animation to the object using a tag that is updated by a network
device that monitors the vat level. At run time, the value of the tag will determine the fill
level of the graphic object.

In the Animation dialog box, to connect the tag to the fill level, you can:

Type the tag name.

Find and select the tag in the Tag Browser.

You can browse while online and connected to a device, or you can browse for tags
from an offline file, such as a PLC program file. For more information, see page 10-8.

Create the tag, if it does not exist.

Create new data server tags in the device or OPC server. For example, in a Logix5000
device, create the tag using RSLogix 5000 programming software.

Create new HMI tags in the Tags editor, in FactoryTalk View Studio. For details, see
“Creating, modifying, and deleting HMI tags” on page 10-21.

Logging tag values

To log tag values, in FactoryTalk View Studio, create data log models that specify which
values to log, and when. For tags in a data log model to be polled and their values logged,
the data log model needs to be started at run time.

For details about setting up data logging, see Chapter 22, Setting up data logging.

Observing tag-related limits

A graphic display can contain up to a total of 3000 connections, whether they originate
from the expressions or the tags.

Each expression associated with an object is counted as one connection regardless of
the number of tags in the expression.

You can type the name of a tag that doesn’t exist. If you do this, to avoid errors at run time,
when you create the tag, make sure you spell the tag’s name consistently.

Use letters in the tag name in addition to numbers. Tag names with over 30 numbers may not
show properly in the tag browser.