GEM2000 Range Gas Analysers
OMGEMN1.41
Copyright 2009 Geotechnical Instruments (UK) Limited
Page 61
can not be zeroed with air, but mixture 2 can be used. The methane and
carbon dioxide can be calibrated with gas mixture 2 at the same time.
Step 8
Attach the flow regulator with gas mixture 2.
Step 9
Attach the regulator to the inlet port and turn on gas.
Do not run the pump.
Step 10
Allow the gas to flow through the unit for approximately two minutes or
until reading stabilises.
Step 11
From the ‘Check Calibration’ screen:
Press
to select ‘Calibration Menu’.
Press
to select ‘Zero Channels’.
Scroll
to ‘Zero O
2
’.
Press
to select ‘Zero O
2
’.
‘USER ZERO COMPLETE’ should be displayed.
When the oxygen channel has been zeroed, the methane and carbon
dioxide channels can be calibrated with the same gas mixture flowing
through the unit.
Step 12
Go on to the Calibrate CH
4
Process with Mixture 2@5%
Always ensure that the CH
4
channel has been zeroed before performing
the methane calibration operation, see above.
Step 13
From the ‘Check Calibration’ screen:
The calibration gas is already flowing through the gas analyser; the
methane reading should be approximately 5% and stable. Do not run
the pump
.
Press
to enter the ‘Calibration Menu’.
Scroll
to ‘Span Channel(s)’.
Press
to select ‘Span Channel(s)’.
Scroll
to ‘Span CH
4
@ 05.0%’ (the value set previously).
Press
to select ‘Span CH
4
@ 05.0%’.
‘CALIBRATION COMPLETE’ should be displayed.
Step 14
Go on to the Calibrate CO
2
Channel Process with Mixture 2 @10%
The carbon dioxide channel can also be calibrated while the same gas
mixture 2 is flowing through the unit.
The carbon dioxide channel
cannot be zeroed.
Step 15
From the ‘Check Calibration’ screen:
Press
to enter the ‘Calibration ‘Menu’.
Scroll
to ‘Span Channel(s)’.
Press
to select ‘Span Channel(s)’.
Scroll
to ‘Span CO
2
@ 10%’ (the value set previously).
Press
to select ‘Span CO
2
@ 10%’.
‘CALIBRATION COMPLETE’ should be displayed.
