39
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Sensor Settings and Calibration
AirLink 6940XP Operator’s Manual
8. For toxic gas cylinders, like Cl
2
, it is important to vent the regulator while installing it onto the
cylinder. Open the regulator by turning the knob counterclockwise and install it onto the
cylinder.
WARNING: Be sure to use a breathing apparatus and to ventilate the area well when
calibrating with high concentrations of toxic gases.
9. After 20-30 seconds, press
ADD
or
SUB
to adjust the reading until the on-screen value
matches the concentration listed on the calibration cylinder.
10. For all calibration gases except Cl
2
, ClO
2
, EtO, and HCl: Let the gas flow for 1 minute.
For Cl
2
calibration gas: Let the gas flow for 3 minutes.
For ClO
2
calibration gas: Let the gas flow for 6 minutes.
For EtO calibration gas: Let the gas flow for 1.5 minutes.
For HCl calibration gas: Let the gas flow for 5 minutes.
11. Press and release
ADD
or
SUB
to adjust the reading until the on-screen value matches the
concentration listed on the calibration cylinder.
For detectors using a surrogate gas, adjust the reading to match the surrogate gas
concentration multiplied by the factor listed in Table 3 on page 38. Some versions will
have to be set above full scale.
NOTE:
For 10.6 eV and 11.7 eV PID sensors, if you are calibrating with a gas other than
isobutylene, you must take the calibration gas’ factor to isobutylene into account
when setting the calibration gas concentration.
NOTE:
Even if the reading does not need adjustment to match the calibration cylinder’s
concentration, you must adjust it up and then back down to reset the Cal field in the
Zero/Calibration Timer Information screen.
