Span Calibration - M&C PMA Series Instruction Manual

The correction factor is calculated as follows:
Correction factor
It is incidental:
100
 = 1,0526
(100 – 5)
For the gas mixture the rectified sum cross sensitivity then is calculated in good approximation :
1,0526 x -0,1123 Vol.% = -0,1182 Vol.%
The rectified sum cross sensitivity with change of sign now can be used for the correction of the
zero calibration. In this case zero had to be adjusted at +0,1182 Vol.%.
In case the cross sensitivities should be ignored in the above mentioned example, this would result
in a relative error of approximately 2%.
After zero calibration the span has to be calibrated too.
N O T E !
16.2

SPAN CALIBRATION

Before span calibration a finished zero calibration is necessary.

Turn the measuring range selection switch to the measuring range in which the calibration
should be done. In case of measuring value concentrations <30% O
clean air in the range of 30% O
switch to 30%. In case of measuring value concentrations >40% O2 a calibration in the
100% range with adequate test gas is recommended. Turn the measuring range selection
switch to 100%.

Connect a flexible PVC- or FEP-hose with the pressure reducer of the N
The pressure reducer should have an output control range of max. 0 – 1,5 bar abs..
C A U T I O N ! The outlet pressure is only allowed to be adjusted at max. 0,1 bar. Other-
wise the measuring cell of the analyser will be destroyed.

Open the bottle valve and than the closed pressure reducer outlet valve and purge the
pressure reducer and the complete hose line for approximately 5 sec. the pressure reducer
and the complete hose line.

Check the adjusted control pressure and reduce if necessary to ≤ 0,1bar, then shut off the
pressure reducer valve again.
www.mc-techgroup.com

=
(100 – O
2
100
-concentration)
2
is recommended. Turn the measuring range selection
PMA20 | 1.00.01
a calibration with dry
2
-zero-gas bottle.
2
19