Geotech GA5000 - Calibration Gases; Calibration Set-Up

GA5000 gas analyser OMGA5KN4.4
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that site, a calibration check could be triggered if the readings measured are different to
what is expected.
 Note: For assistance please contact Technical Support at Geotech on +44(0)1926
338111
9.3 Calibration gases
User calibration of a gas analyser will greatly improve the data accuracy in the range of
the calibration gases used. This may cause less accurate readings of concentrations
outside this calibrated range. Users should select the correct calibration gas for the
expected gas levels on their particular application.
 To improve calibration at lower levels requires the use of gas mixtures 1 and 2.
 To improve higher levels use gas mixture 3.
 For standard CO only 100ppm CO gas is needed.
 For CO (H
2
compensated) both CO 100ppm and H
2
1000ppm gases are needed.
The following table indicates the different gas mixture canisters used for calibration:
Calibration gas
CH
4
CO
2
O
2
Mixture 1
5%
5%
6%
Mixture 2
5%
10%
0%
Mixture 3
60%
40%
0%
Calibration targets for gas cells are dependent on the gas/range and type of cell fitted.
Contact Technical Support for assistance.
These are for general use but other gas concentrations can be used.
 Note: The above gases and most other gas concentrations can be supplied by
Geotech. For further information please contact Sales on +44(0)1926 338111
or email sales@geotech.co.uk.
Warning
Calibration gases can be dangerous.
For each gas used the appropriate material safety data sheet
must be read and understood before proceeding.
9.4 Calibration set-up
Warning
Do NOT attach the gas supply to the gas analyser before
putting the analyser into the ‘Gas Check’ screen. Select
‘Check Spans’ from the ‘Operation Settings’ menu.
The regulator supplied with the calibration kit has been configured to deliver a fixed flow.
As the regulator’s flow is factory set, it only requires a few turns to open, no adjustment is
necessary.