National Instruments BridgeVIEW 用户手册

© National Instruments Corporation

3-1

3

Tag Configuration

This chapter describes tags, the Tag Configuration Editor, how 
you edit tags within the BridgeVIEW system, and includes an activity that 
illustrates how to use the Tag Configuration Editor. Before you can run a 
BridgeVIEW application, you must specify a tag configuration.

What Is a Tag?

 is a data value in the BridgeVIEW Engine. Tags can be used to 

monitor an I/O point, to store a result of a calculation based on other tags, 
or to monitor a tag on another BridgeVIEW Engine. A 

memory tag

 is a tag 

used for user-specified calculations, and a 

network tag

 is a tag remotely 

connected to any type of tag on another BridgeVIEW Engine.

This section defines a tag in terms of its attributes and describes how tag 
attributes affect Engine operations. You can define and configure tags with 
the Tag Configuration Editor, described later in this chapter.

Tag Attributes

The BridgeVIEW Engine manages the Real-Time Database (RTDB) which 
contains information about all the tags in the system. The Engine handles 
the following tasks:

•

Communicates with device servers or other BridgeVIEW Engines

•

Scales tag values

•

Tracks alarms and events associated with tags, system errors and 
events

•

Logs tag values, alarms, events and system messages to disk

You can customize these tasks by configuring each tag with the Tag 
Configuration Editor. The Tag Configuration Editor displays five 
categories of attributes for each tag: general information, connection, 
operations, scaling, and alarms.

Operations, scaling, and alarms attributes describe how the Engine handles 
a tag’s data. Each attribute can be further classified by the effect on a 
running Engine from changing the attribute.