Analytical Industries GPR-1000 ATEX Portable Trace PPM Oxygen Analyzer - Manual (Page 21)

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21. Both the Zero Calibrate and Span Calibrate functions result in the following displays:
PASSED
CALIBRATION
OR
FAILED
CALIBRATION
22. The analyzer returns to the AUTO SAMPLING mode after 30 seconds.
23. 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.
24. Disconnect the span gas line and replace it with the purged sample gas line.
25. Wait 10-15 minutes to ensure the reading is stable and proceed to sampling.
Sampling
GPR-1000 Portable ppm Oxygen Analyzer requires positive pressure to flow the sample gas by the sensor to
measure the oxygen concentration in a sample gas. If not available see Pressure & Flow section.
Note: Prematurely zeroing the analyzer can cause the analyzer to display a negative reading in both the ZERO and
SAMPLE modes.
Procedure:
Following calibration the analyzer returns to the SAMPLE mode after 30 seconds.
1. Select the desired sampling mode - auto or if manual, the range that provides maximum resolution.
2. Use metal tubing to transport the sample gas to the analyzer.
3. The main consideration is to eliminate air leaks which can affect oxygen measurements above or below the
20.9% oxygen concentration in ambient air - ensure the sample gas tubing connections fit tightly into the 1/8”
male NPT to tube adapter, and, the NPT end is taped and securely tightened into the mating male quick
disconnect fittings which mate with the female fittings on the analyzer
4. Assure there are no restrictions in the sample line.
5. Refer to the section on Pressure & Flow to determine the appropriate Application Pressure considerations.
6. For sample gases under positive pressure the user must provide a means of controlling the inlet pressure
between 5-30 psig and the flow of the sample gas between 1-5 SCFH, a flow rate of 2 SCHF is recommended
7. For sample gases under atmospheric or slightly negative pressure an optional sampling pump is recommended
to draw the sample into the analyzer. Generally, no pressure regulation or flow control device is involved.