Configuring Analog Inputs
In this example we'll configure Local I/O Channel 1 to operate as an analog input measuring a pump pressure sensor.
First click on Local I/O Channel 1 in the sidebar to go to the channel settings view:
Then in the view that appears, click Analog Input:
Then click save:
Notice how the status panel at the top has changed to show the Raw Input (the raw value coming into the input) and the System Value:
The System Value is the value that gets written to the channel's configured Tag (in this case, channel1):
The Raw Input and System Value may differ depending on the Dead Band, Rounding, and Calibration:
The additional Units, Range Min, Range Max, and Display Precision parameters affect how the System Value is displayed in gauges:
In this example, we'll enter the following settings for a fictional pump. Make sure to click Save after entering these values.
To ensure accuracy, the Analog Input must be calibrated. To do this click the Calibration button:
The next screen will ask how many calibration points you want to enter. In this example, we'll enter just 2 (the minimum):
Then click Next. The following screen will show you the live Raw Input value and have you enter the Actual Value corresponding to it. For example, say the pressure sensor is driving the input at 5.23 V when at atmospheric pressure (101.325 kPa):
Click Next. Then, change your system to another known value (for example 150 kPa), and enter that as the Actual Value corresponding to the Raw Input value (in this case, 9.82 V):
Click Next again. The final screen will show you a table of the calibration points to be applied:
Click OK to apply these values. This will take you back to the main channel settings view where you can see the calibrated System Value showing: