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Aeroqual AQM60 User Guide
3. Calculate the new offset.
New OFFSET = Old (AQM60 gas reading/Gain factor)
4. Adjust the OFFSET values for each gas sensor by clicking
“Calibration”
“Calibrate OFFSET”
Note: The password to access this section is “password”
5. Select the relevant gas, input the new offset and click OK.
Using External Zero Air Source
A zero calibration can also be performed on the AQM using an external zero air source.
1. Connect a source of zero air to the AQM through the sample port using ¼" Teflon tubing.
Note: The zero air can be humidified using the supplied nafion membrane humidifier as long as there
are low levels of VOCs present in the room.
2. Use a T fitting to ensure the AQM is sampling the gas flow at atmospheric pressure.
3. The zero air should be at least 1.5 LPM
4. Check there is excess flow at the exhaust of the T fitting
5. Allow the AQM to sample until stable readings are obtained (about 30-60 minutes).
6. Calculate the new offset.
New OFFSET = Old (AQM60 gas reading/Gain factor)
7.
Adjust the OFFSET values for each gas sensor by clicking “Calibration”
“Calibrate OFFSET”
Note: The password to access this section is “password”
8. Select the relevant gas, input the new offset and click OK.
4.4. Span Calibration and Check
The sensors in the AQM can be span calibrated by modifying the individual gain factors for each sensor.
Note 1: A zero calibration should always be performed before undertaking a span calibration.
Span gas mixtures should be certified and diluted with air to achieve the required span point. The mixture
can be humidified using the supplied nafion membrane humidifier if the VOC concentration in the room is
low. Excessive gas concentrations should be avoided as these may damage the sensors or cause
contamination of the internal tubing.
Note 2: Always dilute calibration standards with air.
Note 3: Dilution of calibration standards in a balance N2 should be diluted by a factor of at least 50 to
ensure that the change in oxygen does not influence the sensor readings.
Exhaust
USB cable
Nafion
Humidifier
(R21)
Zero Air
Generator
Summary of Contents for AQM60
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