Setting The Column Parameters For Constant Flow Or Constant Pressure; Enter A Flow Or Pressure Program (Optional) - Agilent Technologies 7890 Series Advanced Operation Manual

Setting the column parameters for constant flow or constant pressure

Enter a flow or pressure program (optional)

Advanced Operation Manual
Press [Mode/Type] to see the column mode list.
3
Scroll to the column mode you want. Press [Enter].
4
This completes column mode selection. Next you must
specify the inlet conditions either during the entire run (if
you selected either of the constant modes) or at the
beginning of the run (if you selected either of the ramped
modes).
If the column is defined, you can enter any one of these
quantities—the GC will calculate and display the other two.
For example, you may have selected Constant pressure as the
column mode. You decide to specify, as a starting condition,
the column flow. The GC will compute the pressure
necessary to achieve this flow (as well as the average linear
velocity) and hold this pressure constant during the run.
If you select Constant flow as the mode and specify column
flow as the initial condition, the GC will still calculate the
pressure necessary to achieve this flow, but it will adjust the
pressure as necessary to maintain constant flow.
If the column is not defined, you can enter only pressure.
Constant flow can still be specified, but the GC cannot know
what the flow is.
Press [Col 1] or [Col 2], or press [Aux col #] and enter the
1
column number.
Scroll to the Pressure or Flow or Velocity line.
2
Type the desired initial value, followed by [Enter]. The GC
3
will compute and display the other two values. Adjust
them, if you choose to, by repeating steps
note that changing any one changes all three.
This completes setting the initial carrier gas condition.
If you selected either the ramped pressure or ramped flow
column mode, the column parameter list contains entries for
setting up a ramp program.
You begin with an initial value, either Initial Pressure or Initial
Flow, and an Initial time. At the end of that time, Rate 1 begins
and runs until it reaches Final pressure (or Final flow). It
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Columns and Oven
2 and 3 but
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