Analytical Industries GPR-1900 Series Trace PPB Oxygen Analyzer - Manual (Page 28)

Advanced Instruments Inc.
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22. Repeat steps 20 and 21 until the complete SPAN value has been entered.
23. Save the adjustment value by pressing the ENTER key or abort by pressing the MENU key.
24. Allow approximately 60 seconds for the calibration process while the processor determines whether the signal output or
reading has stabilized within 60% of the full scale low range. Both the Zero Calibrate and Span Calibrate functions result in
the following displays:
PASSED
CALIBRATION OR
FAILED
CALIBRATION
25. If the calibration is successful, the analyzer returns to the SAMPLING mode after 30 seconds.
26. If the calibration is unsuccessful, return to the SAMPLING mode with span gas flowing through the analyzer, make sure the
reading stabilizes and repeat the calibration before concluding the equipment is defective.
27. Before disconnecting the span gas line and connecting the sample gas line, restart if necessary the flow of sample gas and
allow it to flow for 1-2 minutes to purge the air inside the line.
28. For ppm sensors disconnect the span gas line and replace it with a purged, see above, zero or low oxygen content gas line
to purge the sensor down to the desired analysis range as quickly as possible.
29. Wait until the reading is stable and proceed to sampling.
Default Span
The software will set the SPAN adjustment based on the average oxygen reading (actually the sensor’s signal output) at any
specific oxygen concentration. For example, when a span gas is introduced, the micro-processor will display an oxygen reading
within +50% of the span gas value. This feature allows the user to test the sensor’s signal output without removing it from the
sensor housing.
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 appears:
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 DEFAULT SPAN.
6. Press the ENTER key to select the highlighted menu option.
7. The following displays appear and after 3 seconds the system returns to the SAMPLING mode:
FACTORY
DEFAULTS
SET
3.3
PPM
AUTO SAMPLING
100 PPM RANGE
24.5 C
LO1 2 PPM 10 PPM HI2