National Instruments BridgeVIEW 用户手册

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Chapter 3
Tag Configuration
3-28
© National Instruments Corporation
Configure the tag for raw range from zero (Raw Zero Scale) to five 
(Raw Full Scale). Select Linear, and set the engineering range from 
50 (Eng Zero Scale) to 100 (Eng Full Scale).
Example
—
Square Root Scaling
A flow meter measures the flow rate of a liquid using a differential pressure 
reading. The device server provides 4–20 mA readings. The actual flow is 
measured in gallons per minutes (GPM). 4 mA corresponds to 0 GPM; 
20 mA corresponds to 100 GPM.
Configure the tag for raw range from 4 (Raw Zero Scale) to 20 (Raw Full 
Scale). Select Square Root Scaling and set the engineering range from 
0 (Eng Zero Scale) to 100 (Eng Full Scale). 
How Do You Assign Units to an Analog Tag?
Use the Engineering Unit ring to assign units to a tag. If the desired unit 
is not in the list, select Enter New… and enter the desired unit. In the 
previous example, you select units of GPM.
Discrete Tags
The only scaling available for discrete tags is invert scaling. Click the 
Invert Data checkbox, shown in Figure 3-9 to advise the BridgeVIEW 
Engine to invert the discrete value when it communicates with the 
device server.