Sanyo MCO-19M Service Manual page 36

<CO2 zero calibration / O2 zero carlibration
1. Turn the power on and set chamber temperature and set CO2 sensor box temperature in 45
CO2 density in 0.0% and set O2 density in 20.0%. Leave the apparatus until stabilized.
2. Display "Temp/CO2/O2 Calibration" in "Select Tools (1/2)" display.
Access VR3 near CN15 to adjust CO2 sensor reference cell voltage (CO2 Zero) to within 4.00V+/- 0.03V.
Access VR2 hear CN3 to adjust CO2 sensor gas cell voltage (CO2 Span) to within 4.00V+/- 0.03V.
3. Input "0.0" besides "CO2 Zero" column and press MENU key and select "OK".
Press ENTER key to perform CO2 and O2 zero calibration.
The voltages based on CO2 and O2 zer point are memorized.
Note) It is possible to input "0.0" besides "CO2 Zero" column only when CO2 setting is 0.0% and O2 setting is
18.0~22.0%.
It is impossible to input a value besides "O2 Zero" column.
CO2 and O2 zero calibration are done simultaneously. (It is impossible to calibrate CO2 or O2 individually)
When CO2 setting is 0.0%, there is a blank besides "CO2 Span" column.
When O2 setting is 18.0~22.0%, there is a blank besides "O2 Span" column.
<Voltage based on CO2/O2 zero point >
In "Temp/CO2/O2 Calibration (1/2)" display, the display switches to alternately "Temp/CO2/O2 Calibration (1/2)" with
"Temp/CO2/O2 Calibration (2/2)", every press right shift key ( ) or left shift key ( ).
The voltage shown in the right side of "CO2 Ref" column is CO2 sensor reference cell voltage which is memorized in the
zero calibration.
The voltage shown in the right side of "CO2 Gas" column is CO2 sensor gas cell voltage which is memorized in the zero
calibration.
The voltage shown in the right side of "O2 Gas" column is O2 sensor voltage which is memorized in the zero calibration.
CO2 Zero, O2 Zero >
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and set