Advantech I/O Module 5000 Series User Manual page 72

Analog I/O Modules Calibration
4. Issue the Analog Data Out command to the module with an
output value of 4 mA.
5. Check the actual output value at the modules terminals. If this
does not equal 4 mA, use the "Trim" option in the "Calibrate"
submenu to change the actual output. Trim the module until the
mA meter indicates exactly 4 mA, or in case of a voltage meter with
shunt resistor, the meter indicates exactly 1 V. (When calibrating for
20 mA using a voltage meter and shunt resistor, the correct
voltage should be 5 V.)
6. Issue the 4 mA Calibration command to indicate that the output
is calibrated and to store the calibration parameters in the
module's EEPROM.
7. Execute an Analog Data Out command with an output value
of 20 mA. The module's output will be approximately 20 mA.
8. Execute the Trim Calibration command as often as necessary until
the output current is equal to exactly 20 mA.
9. Execute the 20 mA Calibration command to indicate that the
present output is exactly 20 mA. The analog output module
will store its calibration parameters in the unit's EEPROM.
6-10 ADAM 5000 IO modules User's Manual