M&C PMA Series Instruction Manual page 30

The correction factor is calculated as follows:
Correction factor = 
(100 – O
This results in the following correction factor:
100
 = 1.0526
(100 – 5)
For the gas mixture, the corrected total cross sensitivity for 0 vol% oxygen is therefore calculated in good
approximation:
1.0526 x -0.1123 vol% = -0.1182 vol%
The corrected total cross sensitivity with plus/minus sign change can now be used for correction during zero
calibration. In this example, the zero point would have to be adjusted in good approximation to +0.12 vol%.
Neglecting the cross sensitivities in this example would mean a relative error of approx. 2 %.
After zero calibration the full scale value has to be calibrated too.
Note
If the full scale value is not calibrated with 100 vol% oxygen, a correction of the cross sensitivity may be
necessary.
Example: Full scale value calibration with air:
The correction factor is calculated as follows:
Correction factor = 
This results in the following correction factor:
(100 – 20.93)
 = 0.7907
100
30
100
-concentration)
2
(100 – O -concentration)
2
100
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