Setup Modes Of The Coc Inlet; Retention Gaps; Coc Inlet Temperature Control - Agilent Technologies 7890 Series Advanced Operation Manual

Setup modes of the COC inlet

Retention gaps

COC inlet temperature control

Advanced Operation Manual
The COC inlet hardware must be set up for one of three
usages, depending on the type of injection and column size.
• 0.25 mm or 0.32 mm automated on- column. Use
predrilled septa.
• 0.53 mm automatic on- column or retention gap
• 0.2 mm manual
To select the correct hardware for a column and injection
type, refer to Maintaining Your
Because the sample is injected directly onto the column, it is
strongly suggested that a retention gap—or guard column—be
used to protect your column. A retention gap is a
deactivated column that is connected between the inlet and
the analytical column. If you choose to use one, it is
suggested that at least 1 m of retention gap be installed per
1 μL of sample injected. Information on ordering retention
gaps can be found in the Agilent catalog for consumables and
supplies.
If you are using a retention gap and are operating with the
column defined, the length of the retention gap could affect the
calculations for flow and velocity through your column. If your
retention gap is the same inside diameter as your column, it is a
good idea to add the retention gap and column length before
entering the number on the Configure Column parameter list. If
the retention gap inside diameter is larger than your column, this
step may not be necessary.
CryoBlast (optional)
CryoBlast shortens the cycle time between runs. If you have
a CO or N cryogenic valve and the CryoBlast feature, you can
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cool the inlet to –37 °C in either the track oven or temperature
program modes.
The CryoBlast accessory uses coolant from the oven
cryogenic system.
GC.
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Inlets
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