Chapter 3 Detailed Operating Instructions
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4. Turn off the zero gas source and remove the regulator from the
gas cylinder. Proceed to Toxic Gas - Span Calibration - step 4.
Toxic Gas - Span Calibration
NOTE:
Span calibration should not be attempted without zeroing
the sensor first.
NOTE:
Use a 1 liter per minute flow rate regulator when
calibrating.
1. Unscrew and remove the toxic sensor cap (see the IAQ
Monitor instrument diagram in the beginning of this Chapter).
2. Slide the calibration adapter over the wand until the "O" ring in
the bottom of the adapter slides over the handle of the wand.
3.
Thread the regulator onto the cylinder of toxic gas.
4. Using the supplied tubing, connect the toxic gas source to the
toxic gas inlet fitting of the calibration adapter.
5. The arrow keys can be used at this point to adjust the span
value displayed to the desired gas concentration as listed on
the side of the cylinder.
6. Apply the toxic gas
at a rate of 1 liter per minute while
observing the “Current Level” display. Wait for the current level
to stabilize, and then press the RECORD button. The IAQ
Monitor will display “Calibrating…” and begin to count down
from 15 to zero.
7. When the countdown reaches zero, the toxic gas span
calibration value is saved.
8. Turn off the valve on the regulator off and disconnect the toxic
gas source.
Oxygen Zero Adjustment
Performing a zero calibration on the oxygen sensor requires a
cylinder of pure nitrogen, tubing, and a regulator with a 1 liter per
minute flow rate.
