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Chapter 3

Tag Configuration

3-2

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General Attributes

General attributes include data type, maximum length for string and bit 
array tags, and the name, description, and tag group of the tag. The 
BridgeVIEW system supports four types of tags: analog, discrete, string, 
and bit array. These types differ by the inclusion of attributes within the 
operations, scaling, and alarm categories. The tag type is fixed when it is 
created. You must use the tag name to identify a particular tag. For 
information on how to configure the general attribute of a tag, see the 

 section later in this chapter.

Connection Attributes

I/O connection attributes describe where the Engine sends or receives 
values for the tag and how to access that data. These tags have access rights 
of input, output or input/output. To configure the I/O connection attributes 
of a tag, refer to the 

 section later in this chapter.

Memory tags are not connected to a real world I/O point. Memory tags 
provide more complex monitoring, alarming, or control. For more 
information about memory tags, see the 

 section 

later in this chapter.

Operation Attributes

Operation attributes describe additional functionality that the Engine 
performs on a tag or its values. These operations include tasks such as 
setting initial values and enabling logging operations. To configure 
the operation attributes of a tag, refer to the 

 section later in 

this chapter.

Scaling Attributes

Scaling attributes describe what linear scaling function is applied to a tag's 
value. Scaling is useful for converting the range of values from measured 
units into a calculated range. Only analog (numeric) and Bit Array tags 
have Scaling attributes. To configure scaling attributes of a tag, see the 

 section later in this chapter.