Agilent Technologies 7820A

Valves 6
Advanced User Guide 115
Controlling a Valve
From the keyboard
Valves have two positions controlled by the [On] and [Off] keys.
The keyboard commands for two-position valves are:
[Valve #] <scroll to the valve> [On] Rotates valve to one stop
and
[Valve #] <scroll to the valve> [Off] Rotates valve to the other
stop
From the run or clock time tables
The Valve On and Valve Off commands can be run time or clock
time programmed. See “Run Time Programming” on page 12
and “Clock Time Programming” on page 15.
If a valve is rotated by a run time program, it is not
automatically returned to its initial position at the end of the
run. You must program this reset operation yourself.
Gas sampling valve
If a valve is configured as a gas sampling valve, it starts a run
automatically when it is switched to the Inject position. This
can be done with a keyboard command or by a subsequence or
clock table entry. You may have two gas sampling valves
installed.
Carrier in
To column
Sample in
Sample out
LOAD position INJECT position
Loop