G100 Range
OMG100N1.21
Copyright Geotechnical Instruments (UK) Limited
Page
33
3)
Once a stable reading is shown press the soft-key ‘Accept’. A successful span
calibration message will then be displayed. Press the soft-key ‘Accept’ again to
confirm the calibration and ‘Store’ the new user span. Alternatively,
press soft-key
‘Reject’ to exit without change.
Note:
If the calibration failed then try again using a longer purge time or
different target gas.
7.5.3 Zero O
2
Channel:
It is not required to zero the O
2
channel. A span calibration corrects the reading across
the whole range.
7.5.4 Span O
2
Channel:
It is recommended that the O
2
channel is spanned in fresh air with a target concentration
of 20.9%, although other gases and target concentrations can be used if required.
1)
If not already preset, enter the
span target
, i.e. certified concentration of your
calibration gas.
2)
Press the soft-key ‘Start’
and wait for the reading to stabilise. Press the ‘Pump’ key
to draw in fresh air. It can take a couple of minutes to stabilise.
3)
Once a stable reading is shown press the soft-key ‘Accept’. A successful span
calibration message should then be displayed. Press the soft-key ‘Accept’
again to
confirm the calibration and ‘Store’ the new user span. Alternatively,
press
soft-key
‘Reject’ to exit without change.
Note:
If the calibration failed then try again using a longer purge time or different
target gas.
7.5.5 Reset Factory Settings
This option will reset the instrument to its factory programmed calibration characteristics
and will clear the user calibration points for both gas channels.
1)
To reset to factory settings, press ‘Key 1 - Factory
Reset’ from the ‘Calibration’
menu.
User Calibration - Reset
2)
To prevent the user calibration data being accidentally erased the user must
confirm the action by pressing the soft-key ‘Accept’,
or
soft-key
‘Reject’ to exit
without change.