Split/Splitless Inlet Split Mode Minimum Operating Pressures - Agilent Technologies 7820A Advanced User's Manual

Pressure pulse
Pressure
or
Flow
0

Split/Splitless inlet split mode minimum operating pressures

Advanced User Guide
You must press [Prep Run] before doing manual injections in the
pressure pulse modes. See
for details.
You can do column pressure and flow programming when in the
pressure pulse mode. However, the pressure pulse will take
precedence over the column pressure or flow ramp.
Pressure or flow program
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4
The minimum recommended inlet total flow is 20 mL/minute.
When the split/splitless inlet is operated in Split mode, there
will be a minimum pressure at which the inlet can operate.
Typically, low inlet pressures may be required for shorter, wide
bore columns. The minimum pressure is a function of carrier
gas type, total inlet flow, liner design, and possible
contamination of the split vent tube or trap.
A wide bore column requires a much lower inlet pressure than a
typical capillary column to maintain a given flow. Setting the
split ratio (total flow) too high when using a wide bore column
can create an unstable control relationship between the
pressure and flow control loops.
"Pre Run and Prep Run"
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Inlets
on page 25
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