Valve Types - Agilent Technologies 7890 Series Advanced Operation Manual

Valve Types

Advanced Operation Manual
The possible valve types are:
Sampling A two- position (load and inject) valve. In load
position, an external sample stream flows through an
attached (gas sampling) or internal (liquid sampling) loop
and out to waste. In inject position, the filled sampling loop
is inserted into the carrier gas stream. When the valve
switches from Load to Inject, it starts a run if one is not
already in progress. See the example on
Switching A two- position valve with four, six, or more
ports. These are general- purpose valves used for such tasks
as column selection, column isolation, and many others. For
an example of valve control, see
Multiposition Also called a stream selection valve. It is
usually used to select one from a number of gas streams and
feed it to a sampling valve for analysis. It has a special
actuator that advances the valve one position each time it is
activated, or it may be motor driven. An example that
combines a stream selection valve with a gas sampling valve
is on page 223.
Other Could be anything.
Not installed Self- explanatory.
Valves
page 222.
page 223.
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