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Table Of Contents

Scaling Electrical Values to Physical Values

Last Modified: March 11, 2020

Specify settings for a channel to scale electrical values of the device into the physical units of the sensor.

Complete the following steps to apply scaling to your configured sensor.
  1. Click the Configure gear on the channel of the device you wish to scale. The channel configuration dialog opens.
  2. In the Scaling section of the channel configuration dialog, select the scaling type you wish to use.
    Option Description
    Analog input
    • Linear—Apply a linear scaling to the physical signal using slope. For Slope, scale your signal linearly by using the equation y = mx + b, where m is Slope and b is Offset.
    • Sensitivity—Apply a linear scaling to the physical signal using inverse slope. For Sensitivity, scale your signal linearly by using the equation y = x/m + b, where m is Sensitivity and b is Offset.
    • Dynamic Sensitivity—Apply a linear scaling to the physical signal using inverse slope. For Sensitivity, scale your signal linearly by using the equation y = x/m, where m is Sensitivity.
    • Two Point—Provide the minimum and maximum expected electrical values and their corresponding physical values to scale electrical values to physical values (Physical Point 1/Electrical Point 1 and Physical Point 2/Electrical Point 2).

      Two-point scaling uses the formula (Electrical Point 2 – Physical Point 2)/(Electrical Point 1 – Physical Point 1) to calculate gain, and uses the intercept to calculate offset.

      Electrical values are set using an immediate averaging of the signal reading when the From Average button is clicked. The chosen data rate determines the number of samples averaged.

      Data Rate Sample(s) Averaged
      <1 Hz Most recently read sample
      1 Hz–10 Hz Two samples after button clicked
      >20 Hz 100 ms of samples after button clicked
    • Strain—Adjust the Gage Factor and Gage Type to specify sensitivity and strain gage configuration.
    Counter
    • Angular Position Encoder—Set the number of pulses per revolution and initial angle of the encoder. Initial Angle is the value the counter resets to when Restart All Counters is clicked during channel configuration.
    • Linear—Apply a linear scaling to the counter using slope. For Slope, scale your signal linearly by using the equation y = mx + b, where m is Slope and b is Offset.
    • Linear Position Encoder—Set the distance per pulse and initial position of the encoder. Initial Position is the value the counter resets to when Restart All Counters is clicked during channel configuration.
    • Pulse Counter—Set the initial value of pulses. Initial Value is the value the counter resets to when Restart All Counters is clicked during channel configuration.
    • Pulse Encoder—Set the number of pulses per revolution of the encoder.
    Digital input Invert Line—Invert the line in the channel. If applied, the line is at high logic when off and low logic when on.

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