To Change The Hydrogen Sensor Calibration Gas Cylinder - Agilent Technologies Agilent 7890 Series Maintenance Manual

To Change the Hydrogen Sensor Calibration Gas Cylinder

WA R N I N G
Maintaining Your GC
Replace the calibration gas cylinder when you cannot adjust it
to provide the correct flow rate during calibration, or if it
expires.
Connect only the Agilent calibration gas to the hydrogen sensor
fitting. The calibration gas is 2% hydrogen in air and is not
potentially explosive. Gases with higher concentrations of
hydrogen can create a dangerous condition in the oven or damage
the hydrogen sensor.
Make sure the old cylinder is empty.
1
Turn the pressure regulator completely off and set the
2
output pressure as low as possible (full CCW).
3 Remove the pressure regulator from the old cylinder and
install it onto the new cylinder.
Install the new cylinder into the stand.
4
Turn on the pressure in the new cylinder.
5
Open the GC oven door and connect a flowmeter tube to the
6
sensor tube in the oven.
meter to the
hydrogen sensor
tube next to the
oven heater shroud
Press [Options] then go to Calibration > Hydrogen Sensor and
7
press [Enter].
Scroll to Start Calibration Cycle? and press [On/Yes]. The
8
calibration cycle begins. The hydrogen sensor module will
wait to stabilize, then will begin to send calibration gas
across the sensor.
3
Maintaining the GC
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