PROGRAMMING THE AREARAE
4-14
3. This completes the single-gas calibration procedure for one
sensor. The display shows the single-gas calibration
submenu for a user to select another sensor or move to the
next submenu, Modify Span Gas Value.
4. Turn the gas flow off. Disconnect the calibration tube from
the AreaRAE Steel.
5. Repeat Step 1 through Step 3 to calibrate the next sensor.
6. Press [MODE] to stop the countdown timer and abort the
calibration during Step 1. If a sensor fails calibration, the
sensor name and the error message
“
failed, continue?
”
appears. Press [N/-] or [MODE] to abort calibration and
move to the next submenu item. Press [Y/+] to continue
single-gas calibration. In either case, the current calibration
data is not changed.
Oxygen Sensor Calibration
The oxygen sensor calibration is slightly different from the other
sensors. The oxygen sensor measures a range of 0 to 30% of
oxygen in the air. During fresh air calibration, the oxygen
sensor is calibrated to a fixed percentage of 20.9% oxygen.
During single-sensor calibration, you may supply a pure
nitrogen gas so the oxygen sensor may be calibrated to 0%
oxygen. You may also supply other span concentrations of the
oxygen (for example, 19.5%), to calibrate the oxygen sensor.
When “0% oxygen?” appears, enter [Y/+] if the pure nitrogen
gas is used to calibrate the oxygen sensor. Otherwise, enter
[N/-] to calibrate the oxygen sensor to another span oxygen
value. During either single- or multiple-sensor calibration, the
oxygen sensor is calibrated to the span value. (See Section
4.4.5: Modify Span Gas Value.)
Note:
After a 0% oxygen calibration, you must perform a fresh
air calibration to ensure that the oxygen sensor is calibrated
correctly.
Calibration Time Stamp
When a single- or multiple-sensor calibration is performed, a
time stamp is stored in the non-volatile memory. This
information is included in the datalogging report.
