AirLink 6940XP Operator’s Manual
Sensor Settings and Calibration
•
40
12. When calibration is complete, remove the calibration cup from the sensor housing and
reinstall the rain guard.
13. Press
MENU
or
BACK
to return to the Sensor Settings menu.
Calibrating the Sensor (Auto Cal)
Each sensor can be manually or automatically calibrated, depending on the sensor’s calibration
method (see page 48 for setting the calibration method). If the sensor calibration method is set to
Manual, see “Calibrating the Sensor (Manual Cal)” on page 37.
Sensors should ONLY be calibrated after completion of the zero process.
If the sensor has already been manually calibrated, skip to “Sensor Radio Address” on page 44.
NOTE:
LEL and CO
2
- LEL and CO
2
versions of the AirLink 6940XP can only be calibrated
using Auto Cal (see the next section).
HCl - It is recommended that the HCl version only be calibrated using Auto Cal, but
Manual Cal can be used if desired.
O
2
- If calibrating with 100% N
2
, you must use Manual Cal. To calibrate using Auto
Cal, a gas concentration between 10 and 18% O
2
is recommended.
Calibration Frequency
A calibration should be performed EVERY thirty (30) days. Days since the last calibration should
NEVER exceed ninety (90) days. RKI recommends that you calibrate your device regularly to
ensure proper functionality and a safe work environment.
Materials
• 0.5 LPM fixed flow regulator with knob and calibration tubing
WARNING: If calibrating with Cl
2
or HCl, a regulator must be dedicated for use with that gas
only. Do not use that dedicated regulator for any other gases, particularly H
2
S.
• calibration cup
• calibration cylinder or gas generator (For O
2
sensors, RKI recommends using 100% N
2
.
For all other sensors, RKI recommends using 50% of the full scale value of your detected
gas.)
NOTE:
Some detected gases use surrogate gases for calibration. Detected gases needing a
surrogate gas for calibration are listed below. If you are using a surrogate gas for
calibration, that surrogate gas concentration multiplied by the factor listed in Table 4
should equal about 50% of the detected gas’ full scale.
