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To change the gas type, click on the down
arrow to the right of the gas setting and
select the new gas type.
Once the gas type is chosen, enter the
calibration gas composition, including the
values for any toxic gases in the cylinder in
terms of parts-per-million (ppm) and the
oxygen level in terms of percent volume
(%). To change a gas value use the arrows
to the right of the gas value input box to
increase or decrease the value until it
matches the value given on the gas
cylinder.
Since a common calibration gas mixture
includes CO and H
2
S, a CO/H
2
S option is
available that offers distinct settings for CO
and H
2
S. This allows the dock to process
CO, CO- and H
2
S units without changing the
gas setting.
Note: Due to cross-sensitivity issues,
CO+ detectors must be calibrated with
CO calibration gas only. A CO+ detector
placed in a dock that is configured for
CO/H2S will automatically fail to process.
The IQ System will automatically fail any
detector that is processed when the
calibration gas type fails to match the
sensor type.
Calibration values
shown in the Gas Value column must
match those appearing on the calibration
gas cylinder(s) that will be used to
calibrate the detector. Non-matching
calibration gas and calibration gas value
settings will lead to inaccurate and
potentially dangerous readings.
Special Instructions: Gas
Configuration, Oxygen Detectors
An oxygen detector can be processed by
the IQ Express in a fresh air atmosphere
without the use of calibration gas, but an
optional bump test is available to verify
oxygen sensor response. The O2 Bump
and Calibration is automatically enabled at
the factory. If the user wishes to bypass the
oxygen bump test, the O2 Bump and
Calibration option can be disabled by
deselecting the “Enable….: check box at the
bottom of the Gas Configuration settings. .
Each calibration gas type includes an
oxygen setting that should reflect the
amount of oxygen in the calibration gas
cylinder (typically 18%).
With the O2 Bump and Calibration option
enabled, when an oxygen detector is placed
in the dock, the system will proceed with an
oxygen bump test based on the O
2
gas
value that has been entered. If the bump
test fails, the dock will show a warning on
the screen that the instrument has failed the
test.
A special case exists when a cylinder of
0.0% oxygen calibration gas is connected to
the dock. If the O2 Gas Value is set to 0.0%
oxygen and the instrument fails the bump
test, it will automatically attempt a full zero
calibration at 0.0% oxygen.
For all other levels of calibration gas
(>0.0%), the oxygen bump test is the only
test available. The zero calibration of the
oxygen sensor is only available with
calibration gas containing 0.0% O
2
.
To disable the O2 Bump and Calibration
deselect the option.
