PROGRAMMING
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4.4.2 Span Calibration
This procedure is the second type of sensor calibration. A
bottle of standard reference gas (span gas) and a Tedlar bag are
needed to perform this procedure. First, fill the Tedlar bag with
the span gas. Connect the calibration adapter to the inlet port of
the UltraRAE Monitor, and connect the tube to the Tedlar bag.
Before executing a span calibration, make sure the span value
has been set correctly (see next sub-menu).
1. Advance to the next calibration phase (Span calib), the
display should show “Span calib?
2. Insert a new RAE-SEP tube into the monitor. (Note: For
VOC calibration, there is no need to use a new VOC tube).
First fill the Tedlar bag (Do not overfill with span gas).
Then connect the bag to the inlet port.
3. Press the
[Y/+]
key. The monitor will identify the inserted
tube and display the tube name. If the tube cannot be
identified, the tube can be manually selected by responding
with
[N/-]
until the correct tube name is displayed.
4. Press the
[Y/+]
key when the correct gas name is shown.
The display shows “Span gas = xx ppm?” If incorrect, press
the
[N/-]
key and correct the span gas value. When the span
gas value is correct, open the valve to the Tedlar bag and
press the
[Y/+]
key to start the calibration. The display
reminds the user to “Apply gas now!” and begins a
countdown timer showing the number of remaining seconds.
When the count down timer reaches zero, the display shows
the calibrated value. Turn off the gas and press
[MODE]
key to exit calibration
5. This completes the calibration procedure for a gas. The
display shows the next calibration sub-menu.
6. Disconnect the calibration adapter and Tedlar bag.
7. Press the
[N/-]
or
[MODE]
key to abort more calibration
and move directly to the next sub-menu item. The current
calibration data will be saved automatically.
