5
The current value will be blinking on the LCD. Press Up/DP/
WB to increase the value, or M
N
X
/AVG/Down to decrease it.
Press the SET button again to enter “P1.2” to set the CO
2
alarm lower limit (when the level drops below this, the alarm
will automatically stop). The current value will be blinking on
the LCD. Press Up/DP/WB to increase the value, or M
N
X
/
AVG/Down to decrease it. Press the SET button to save the
values, or CAL/ESC to exit without saving.
The meter features an audible alarm to warn by emitting
80dB beeps when the CO
2
concentration exceeds the upper-
limit. The alarm can be stopped by pressing any button ex-
cept SET. It will also stop when readings fall below the lower
limit value.
P3.0 Set Temperature Units
From the P1.0 display, press Up/DP/WB to change to the
P3.0 screen (“Unit” will display on the LCD). Press the SET
button to enter “P3.1” to set the temperature units. The cur-
rent units, “°C” or “°F”, will be displayed on the lower left area
of the LCD. Press Up/DP/WB or M
N
X
/AVG/Down to switch
between “°C” and “°F”. Press the SET button to save the set-
ting, or CAL/ESC to exit without saving.
P4.0 ABC Selection
ABC (Automatic Baseline Calibration) implements baseline
calibration to eliminate the zero drift of the infrared sensor.
The ABC function default is off when turning on the meter. To
enable it, press M
N
X
/AVG/Down from P1.0 or Up/DP/WB from
P3.0 to change to the P4.0 screen, (“Abc” will display on the
LCD). Press SET to enter P4.1 (“dis” will display on the
LCD). Press Up/DP/WB or M
N
X
/AVG/Down to switch to
“En” (enabled). Press the SET button to save the setting, or
CAL/ESC to exit without saving.
To exit setup, press the CAL/ESC button.
CO
2
Calibration
The meter is calibrated at the factory to a standard 400ppm
CO
2
concentration. It is suggested to do either ABC or a
manual calibration regularly to maintain good accuracy. The