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3. Calibration
There are two calibration methods: Ambient Air (300-600ppm) and Nitrogen (0-200ppm).
By pressing the temperature unit button
for 5 seconds, the monitor will enter CO2 calibration
mode. While in calibration mode, press the temperature button
quickly to switch between
AIR (Ambient Air Calibration) or N2 (Nitrogen Calibration). Press the power
button
to confirm.
Zero calibration requires 100% nitrogen (0% CO2) calibration gas, a flow regulator and flexible
tubing.
The Atmospheric calibration will not require additional materials but must be performed in
outdoor (300-600ppm fresh air) during the entire procedure.
See Section 2.2 Menu and Configuration Settings, to change settings.
4. Alarm Threshold
There are default thresholds: 5,000 ppm CO2 (low alarm) and 1% CO2 (Short Term Exposure Limit)
(high alarm). The alarm thresholds can be changed dependent on the user, to L0.5 (5000 ppm),
L0.5T (5000 ppm TWA), L1.0 (10000 ppm), L1.5 (15000 ppm), or L3.0 (30000 ppm).
If the measured CO2 value exceeds the define Low Alarm threshold, the alarm LED will flash red
at 2Hz and the audio alarm
“de de … de de …” will sound. If the CO2 level exceeds the
High Alarm threshold, the LED will flash faster and the audio alarm will increase. To alert
users in a noisy environment, the monitor will also vibrate.
See Section 2.2 Menu and Configuration Settings, to change settings.
5. Automatic Atmospheric Pressure Compensation
The displayed CO2 level is affected by atmospheric pressure or change in altitude. To insure
maximum accuracy, this monitor has automatic atmospheric pressure compensation for CO2
concentrations by means of a digital atmospheric pressure sensor integrated in the unit. No
calculations or maintenance is required.
See Section 2.2 Menu and Configuration Settings, to change settings.
