Analytical Industries GPR-1600 MS Series PPB Oxygen Analyzer - Manual (Page 32)

Advanced Instruments Inc.
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Default Zero:
The software will eliminate any previous zero calibration adjustment and display the actual the signal output of the sensor at
any specific oxygen concentration. For example, assuming a zero gas is introduced, the display will reflect an oxygen reading
representing basically the zero calibration adjustment as described above. This feature allows the user to test the sensor’s signal
output without removing it from the sensor housing.
The DEFAULT ZERO function is recommended before performing the initial zero calibration or when troubleshooting the
analyzer.
Output Zero:
In rare instances the 4-20mA signal output may not agree to the reading displayed by the LCD. This feature enables the user to
adjust the 4mA signal output when the LCD displays 00.00. Compute the adjustment value as described in Appendix B or
consult the factory.
Note: Adjust the 20mA signal output with the OUTPUT SPAN option described below. The true adjustment value must be
determined empirically by trial and error. Adjust the initial adjustment value for additional percent errors.
Procedure:
1. Access the MAIN MENU by pressing the MENU key.
2. Advance the reverse shade cursor using the ARROW keys to highlight CALIBRATION.
3. Press the ENTER key to select the highlighted menu option.
4. The following displays appear:
MAIN MENU
AUTO SAMPLE
MANUAL SAMPLE
CALIBRATION
CONFIG ALARMS
BYPASS ALARMS
>>> CALIBRATION
SPAN CALIBRATE
ZERO CALIBRATE
DEFAULT SPAN
DEFAULT ZERO
OUTPUT SPAN
OUTPUT ZERO
5. Advance the reverse shade cursor using the ARROW keys to highlight OUTPUT ZERO.
6. Press the ENTER key to select the highlighted menu option.
7. The following display appears
100.0
OUTPUT ZERO OFFSET
PRESS UP OR DOWN
TO CHANGE VALUE
ENTER TO SAVE
MENU TO RETURN
8. Compute the adjustment value as described in Appendix B. Note: The true adjustment value must be determined
empirically by trial and error. Adjust the initial adjustment value for additional percent errors.
090.0
OUTPUT ZERO OFFSET
PRESS UP OR DOWN
TO CHANGE VALUE
ENTER TO SAVE
MENU TO RETURN