31
CO
2
calibration
Span setting
Span setting should be done under stable condition of temperature, humidity, and CO
2
density.
1.
Press the calibration key (CAL) for about 5 seconds.
2.
The third digit on the digital temperature indicator flashes, and the digital CO
2
density indicator goes
out.
3.
Press the calibration key (CAL) once again.
4.
The third digit on the digital CO
2
density indicator flashes, and the digital temperature indicator goes
out.
5.
Set the present correct CO
2
density with the digit shift key ( ) and numerical value shift key ( ),
then press the enter key (ENT).
6.
The unit automatically reverts to the display mode.
Note:
This calibration is available when the setting of CO
2
density is 2 % or more.
[Example]
For an internal CO
2
density of 5.0 % (setting) and a measured value of 4.5 %.
1.
Press the calibration key (CAL) for about 5 seconds.
2.
The third digit on the digital temperature indicator flashes, and the digital CO
2
density indicator goes
out.
3.
Press the calibration key (CAL) once again.
4.
The third digit on the digital CO
2
density indicator flashes, and the digital temperature indicator goes
out.
5.
Set the present correct CO
2
density (4.5 %) with the digit shift key ( ) and numerical value shift key
( ), then press the enter key (ENT).
6.
The unit automatically reverts to the display mode.
