Teledyne API Model 300M CO Analyzer Instruction Manual, 04033, Rev. A
9.2 A/D - D/A Calibration Procedure
Due to the stability of modern electronics, this procedure should not have to be performed more than once a year or whenever a major
To calibrate the voltage output, do the following: 4 - 20 mA current output calibration procedure should follow after voltage calibration.
1.Press
2.Enter Diagnostic password and press NEXT until D/A CALIBRATION appears in the display and press ENTR.
3.Press ADC to perform the A/D Cal.
4.The M300M display will read "ADJUST ZERO:A/D=xx.x MV." Put the probe of a voltmeter between TP3 (AGND) and TP9 (DAC #0) on the top of the V/F card (See Drawing 00514, Appendix C).
5.The value displayed by the voltmeter should be close (± 2 mV) to the value on the M300M display. If they are not close then the V/F card has probably been configured improperly.
6.Adjust the Zero pot (R27) on the V/F card until the value on the M300M display matches the value on the voltmeter to within ± 2 mV.
NOTE
When adjusting R27, the value on the M300M display will change,
the value on the voltmeter will remain constant.
7.Press ENTR.
8.The M300M display will now read "ADJUST GAIN:A/D=xx.x MV."
9.Adjust the Span pot (R31) on the V/F card until the value on the M300M display matches the value on the voltmeter to within ± 2 mV.
10.Press ENTR.
11.The ADC is now calibrated and the M300M will automatically calibrate all the DAC’s. This process takes only a few seconds.
12.Press EXIT 4 times to return to the sample menu.
