National Instruments BridgeVIEW 用户手册

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Chapter 3
Tag Configuration
© National Instruments Corporation
3-3
Alarm Attributes
Alarm attributes describe abnormal process conditions for a given tag. 
Alarms are useful for notifying users of abnormal conditions. For example, 
if an analog tag measures the volume of a tank, a HI alarm can be used to 
indicate that the tank is full and an operator must perform some action 
and acknowledge this state before processing can proceed. For information 
on how to configure alarming attributes of a tag, see the 
 section 
later in this chapter.
Static vs. Dynamic Attributes
Tag attributes are classified as either static or dynamic attributes. 
 require you to restart the Engine when you change them from 
the Tag Configuration Editor. A static attribute change is marked with 
a solid diamond in the Tag Configuration Editor. Examples of static 
attributes are general attributes and I/O connection attributes, such as 
server, device, or item.
 do not require the Engine to restart. The Tag 
Configuration Editor can change a dynamic tag attribute in a running 
Engine. A dynamic attribute change is marked with a hollow diamond in 
the Tag Configuration Editor. Examples of dynamic attributes include 
enabling logging operations, alarm attributes, and some scaling attributes. 
For more information about dynamic tag attributes, see the 
 section of Chapter 7, 
.
What Is the Tag Configuration Editor?
The Tag Configuration Editor is a tool that assists you in configuring all 
the parameters of the BridgeVIEW Engine. The chief component of this 
tool is the configuration of all tags in the system. Other configuration 
components include Alarm and Event Logging, and Historical Logging.
To start the Tag Configuration Editor, select Project»Tag» 
Configuration…
 from the menu bar of an open VI. Figure 3-1 shows 
the Tag Configuration Editor with 
tanks.scf
 loaded.