Pulsed Splitless Mode; Gas Saver Mode - Agilent Technologies 6890 Series Service Manual

210 Split/Splitless Inlet
EPC inlet
Flow
limiting
frit
PV1
Proportional
valve 1
Safety shutdown mode:
Proportional valve 1 closed
Proportional valve 2 open
On/off valve open
Figure 210-2

Pulsed splitless mode

For EPC inlets set to pulsed splitless mode, the column head pressure is
increased to some selected value and selected time period prior to sample
introduction. Like the split mode, the increased flow through the column
during the injection period minimizes sample losses in glass liners.

Gas saver mode

For EPC inlets, Gas Saver mode may be used in splitless or split mode of
operation for conservation of split and inlet purge flows when not in use or
in between runs. A gas saver flow rate and start time can be set independently
of normal flow rates being used.
4 of 30
Septum holder
Flow
sensor
4 mL/min
FS
Pressure
EPC control splitless mode flow diagram (pre-run to purge time).
Inlets
Agilent 6890 Gas Chromatograph Service Manual
Septum purge
regulator (not
adjustable)
Septum purge
SPR
PS
3 mL/min
sensor
V
PV2
Valve
Proportional
closed
valve 2
Inlet vent (split)
To Detector
Jun 2001