PROGRAMMING P3.o TEMPERATURE SCALE
Press (
) or (
) in P1.o to access P3.o for setting up
temperature scale (Fig. 12). Press (
) and it goes into P3.1 with
blinking °C or °F current set (Fig.13) on the lower left display. To
switch °C or °F,
Press (
) and (
). Then press (
) to save the setting or
(
) without saving and return to P3.o.
CO
2
CALIBRATION
The meter defaults to be calibrated manually in the ambient air where
CO
2
concentration is around 400ppm. It’s suggested to do manual
calibration regularly to maintain good accuracy.
CAUTION:
Do not calibrate the meter in air with unknown CO
2
concentration. Otherwise, it will be calibrated as 400ppm
by default and will lead to inaccurate measurements.
CALIBRATION SITE
The manual calibration is suggested to be done in fresh outdoor air
that is well ventilated and in sunny weather.
PROCEDURE
Place the meter in the calibration site. Turn on the meter and hold
down (
) and (
) simultaneously to enter CO
2
calibration
mode (Fig.14). 400ppm and “CAL” are blinking on the LCD while
performing calibration.
Wait about 10 minutes until the blinking stops and the calibration is
completed automatically and returns back to normal mode.
To abort the calibration, turn off the meter at any time.
NOTE:
Ensure the batteries are with full voltage during the calibration
cycle to prevent interruption or failed calibration.
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