Menu navigation, Main menu, Range selection – Analytical Industries GPR-1200 ATEX Portable Trace PPM Oxygen Analyzer User Manual
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Menu Navigation
The five (5) pushbuttons located on the front of the analyzer operate the micro-processor:
1. Blue ENTER (select)
2. Yellow UP ARROW
3. Yellow DOWN ARROW
4. Green MENU (escape)
5. Red ON/OFF
Main Menu
Access the MAIN MENU by pressing the MENU key:
MAIN MENU
AUTO SAMPLE
MANUAL SAMPLE
CALIBRATION
Range Selection
The analyzer is equipped with five (5) standard measuring ranges (see specification) and provides users with a choice of
sampling modes. By accessing the MAIN MENU, users may select either the AUTO SAMPLING (ranging) or MANUAL SAMPLING
(to lock on a single range) mode.
Note: For calibration purposes, use of the AUTO SAMPLE mode is recommended. However, the user can select the full scale
MANUAL SAMPLE RANGE for calibration as dictated by the accuracy of the analysis required – for example, a span gas with an
80 ppm oxygen concentration with the balance nitrogen would dictate the use of the 0-100 ppm full scale range for calibration
and a 0-10 ppm measuring range.
Auto Sampling:
1. Access the MAIN MENU by pressing the MENU key.
2. Advance the reverse shade cursor to highlight AUTO SAMPLE.
3. Press the ENTER key to select the highlighted menu option.
4. The display returns to the sampling mode:
MAIN MENU
AUTO SAMPLE
MANUAL SAMPLE
CALIBRATION
>>>
3.3
PPM
AUTO SAMPLING
10 PPM RANGE
24.5 C
The display will shift to the next higher range when the oxygen reading (actually the sensor’s signal output) exceeds 99.9% of
the upper limit of the current range. The display will shift to the next lower range when the oxygen reading drops to 85% of the
upper limit of the next lower range.