General Tools and Instruments CDM7722 - Manual (Page 11)

Wait about 5 minutes until the blinking
stops and the calibration is completed
automatically and return to normal
mode.
To abort the calibration, press for
more than 1 second. RESET RESET
fresh air where CO level is around 400
2
ppm.
The manual calibration is suggested to
be done in outdoor area with ventilating
Do not calibrate in places crowded
with people or close to where with high
CO concentration such as ventilating
2
outlets or fireplaces.
Fig. 16
Place the meter in the calibration site.
Turn on the meter and hold down
and simultaneously to enter CO
2
calibration mode (Fig.16). 400ppm and
“CAL” are blinking on the LCD while
performing calibration.
CAL
ESC
CAL
ESC
DP/WB
CO 2
PPM
Manual Calibration
10
ABC (Automatic Baseline Calibration)
ABC is to calibrate the meter at the
minimum CO reading detected during
2
7 days continuous monitoring (power
on). It is supposed that the ventilating
area can have fresh air with CO level
2
in around 400ppm during a period of
time. It’s not suitable to implement
ABC in close area with higher CO level.
2
The ABC default is off. To enable the
function, please refer to SETUP P4.0.