Additional Notes On Column Configuration; To Configure Multiple Columns - Agilent Technologies 8890 Operation Manual

11 Configuration
12 Select Apply. This saves the changes to the GC.

Additional notes on column configuration

You should check configurations for all columns to verify that they specify the correct pressure
control device at each end. The GC uses this information to determine the flow path of the
carrier gas. Only configure columns that are in current use in your GC's carrier gas flow path.
Unused columns configured with the same pressure control device as a column in the current
flow path cause incorrect flow results.
It is possible, and sometimes appropriate, to configure both installed columns to the same
inlet.
When splitters or unions exist in the carrier gas flow path, without a GC's pressure control
device monitoring the common junction point, the individual column flows cannot be
controlled directly by the GC. The GC can only control the inlet pressure of the upstream
column whose inlet end is attached to a GC's pressure control device. A column flow
calculator available from Agilent, and provided with Agilent capillary flow devices, is used for
determining pressures and flows at this type of junction.
Some pneumatic setpoints change with oven temperature because of changes in gas
viscosity. This may confuse users who observe pneumatics setpoints changing when their
oven temperature changes. However, the flow condition in the column remains as specified by
the column mode (constant flow or pressure, ramped flow or pressure) and the initial setpoint
values.

To configure multiple columns

To configure multiple columns, repeat the procedure above for each column.
These are the available choices for Inlet, Outlet, and Thermal zone. Some will not appear on
your GC if the specific hardware is not installed.
Table 16 Choices for column configuration
Inlet
Front inlet
Back inlet
Aux# 1 through 9
PCM A, B, and C
Aux PCM A, B, and C
Operation Manual
• Date Manufactured
• Serial Number
• Part Number
• Phase Tag
• Column ID Lock. If using an optional barcode scanner, this will be set to Locked by the
data system. Normally, set to Unlocked when not using a barcode scanner.
Outlet
Front detector
Back detector
MSD
Aux detector 1
Aux detector 2
Thermal zone
GC oven
Auxiliary oven
Aux thermal zone 1
Aux thermal zone 2
Aux thermal zone 3
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