Examples; Using An Aux Epc Channel To Supply Purge Gas To A Splitter; Using The Pcm Channels - Agilent Technologies 7890 Series Advanced Operation Manual

2
Flow and Pressure Modules

Examples

1. Using an Aux EPC channel to supply purge gas to a splitter

Split/splitless inlet
30 m x 0.25 mm x 0.25 µm HP-MS5

2. Using the PCM channels

30
An Aux EPC channel operates only in the forward- pressure
mode; it provides a constant pressure at its outlet. It is used
to provide gas to some other device, such as a splitter with
a makeup gas input.
Aux EPC
In this configuration, the gas eluting from the column is
divided among three detectors. Because the resulting flows
can be quite small, makeup gas is added at the splitter. An
Aux EPC channel provides it.
Assume that we are using channel Aux epc 1 as the makeup
source. The gas is plumbed to the leftmost (as seen from the
back of the GC) fitting on the proper module. The outlet
tubing for this channel goes to the splitter inside the
oven—an extension tube may be needed to reach this far.
The medium frit is probably appropriate for this application.
Rather than have the makeup gas flowing all the time,
consider turning it on and off with run time commands.
The two channels in a PCM are different. Channel 1 is used
to supply a pressure. Channel 2 may be used in the same
way, but can also be used to maintain a pressure by
reversing the input and output connections.
µECD FPD
0.507 m x 0.10 mm x 0 µm
MSD
0.532 m x 0.18 mm x 0 µm
1.444 m x 0.18 mm x 0 µm
Advanced Operation Manual