Chapter 3
Tag Configuration
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National Instruments Corporation
3-27
Analog Tags
You can define the raw range and engineering range for a tag to perform
simple conversions between the two ranges. The raw range, defined by
Raw Full Scale and Raw Zero Scale, refers to the values used by the
device server. Engineering range, defined by Engineering Full Scale
and Engineering Zero Scale, refers to the values used by the BridgeVIEW
Engine and HMI. Pull down the Scaling ring and select Linear to enable
a linear (mx + b) conversion between raw and engineering ranges. Select
Square Root to enable a square root conversion between the raw and
engineering ranges. Figure 3-8 shows the Scaling tab of the Analog Tag
Configuration dialog box.
Figure 3-8.
Analog Tag Scaling Dialog Box
The following examples describe linear and square root scaling.
Example
Linear Scaling
A device server returns a simple voltage from 0 to 5 V. The voltage is
related to a position sensor, and the real-world position is measured in
centimeters, with 0 volts mapped to 50 cm and 5 V mapped to 100 cm.