82 Calibrating Measured Values
WAGO-I/O-SYSTEM 750
750-564 4AO U/I
Manual
Version 1.0.0
2.
Enable user calibration under
Calibration
.
3.
Set the value for the calibration offset to “0”.
4.
Set the value for the calibration gain to “1”.
5.
Specify the first process value.
6.
Read the expected output voltage on the measuring instrument.
Example:
Process value 1 (y1) = 1 V
At 1 V, the expected output voltage (x1) = 0.97 V
7.
Specify the second process value.
8.
Read the expected output voltage on the measuring instrument.
Example:
Process value 2 (y2) = 9 V
At 9 V, the expected output voltage (x2) = 9.05 V
9.
Insert all calculated values into the respective equations.
You obtain the values for the calibration gain and offset sought as the
result.
Example:
Calibration gain:
m = (y2 – y1) / (x2 – x1)
m = (9 V – 1 V) / (9.05 V – 0.97 V) = 0.99
Calibration offset:
b = y1 – (m × x1)
b = 1 V
−
(0.99 × 0.97 V) = 0.04 V
10. Enter the calculated gain value (“0.99”) in WAGO-I/O-
CHECK
.
11. Convert the result for the calibration offset based on the process value
resolution:
0.04 V / 0.000152579 V per digit = 262 digits
12. Enter the calculated offset value (“262”) in WAGO-I/O-
CHECK.
