Servomex SERVOTOUGH Oxy, Operator'S Manual

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01910001B_8 © Servomex Group Limited. 2020
61
Note:
Example:
If you are
measuring 10% Oxygen in a background of 70% Hydrogen and 20% Carbon
Dioxide the correction factor would be:
The correction factor assumes 100% of background gas, so you must firstly correct for
the nominal process oxygen concentration:
Total background concentration = 70% + 20% = 90% Correct background
concentrations for 0% oxygen:
(100% / 90%) x 70% = 77.8% Hydrogen
(100% / 90%) x 20% = 22.2% Carbon Dioxide
For 100% Hydrogen the correction is 0.26, so for 77.8% it is 0.202
For 100% Carbon Dioxide the correction is
-
0.30, so for 22.2% it is
-
0.067
So the total correction factor in this case is
-
0.067 + 0.202 = 0.135
5.18.2
Entering a cross
-
interference compensation
Note: Cross-
interference compensation is disabled during calibration, and is not applied to
the values shown in Figure 75. All other outputs (that is, serial or mA outputs) remain
compensated.
Use the following procedure to enter a compensa�on to correct for an O
2
(oxygen) measurement error:
1.
Select:
Set Up
Interference
2.
The offset value shown on the X
-
Interference offset screen is the correc�on which will
be applied to O
2
(oxygen) sample measurements before they are displayed (or output).
3.
Edit the displayed offset.
Figure
58 -
The X
-
Interference offset screen
5.19
Selecting display units
You can change the measurement units shown on the display (and output). The following display units
are supported: