To Bakeout The Npd - Agilent Technologies Agilent 7890 Series Maintenance Manual

14
Maintaining the NPD

To Bakeout the NPD

WA R N I N G
WA R N I N G
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If using hydrogen as a carrier gas, turn off the hydrogen supply
and cap the end of the column to prevent an oven explosion.
Bakeout the NPD with the column installed or
1
uninstalled. If uninstalled, gather the following (see
"Consumables and Parts for the NPD"
• Capillary adapter (adaptable NPD only)
• Column nut
• No- hole ferrule
Load the GC maintenance method
2
become ready.
Be careful! The detector may be hot enough to cause burns. If the
detector is hot, wear heat-resistant gloves to protect your hands.
Set the bead voltage to 0, then turn it Off.
3
If the column is uninstalled, plug the detector connection
4
with the capillary adapter, column nut, and no- hole
ferrule.
Maintain inert carrier gas flow through the column, or
remove the column from the GC.
5 Set normal operating flows.
Set the detector temperature at 25 °C above the typical
6
method setpoint temperature.
Set the oven temperature to 250 °C or 25 °C above the
7
normal maximum operating temperature. Do not exceed
the column's temperature limit.
Hold at temperature for 15 to 30 minutes.
8
If the column is not installed in the NPD, install it. (See
9
"To Install a Capillary Column in the NPD"
10 Restore the analytical method and allow the NPD to
equilibrate at operating temperatures and flows for 10 to
30 minutes.
11 Check the NPD leakage current. See
Leakage Current"
and wait for the GC to
"To Check the NPD
on page 285.
on page 260):
on page 268.)
Maintaining Your GC