Programming; Run Time Programming; Using Run Time Events - Agilent Technologies 7890 Series Advanced Operation Manual

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Programming

Run Time Programming

Using run time events

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Run time programming during a method allows certain
setpoints to change automatically during a run as a function
of the chromatographic run time. Thus an event that is
programmed to occur at 2 minutes will occur 2 minutes
after every injection.
Its uses include:
• Controlling column switching or other valves
• Changing analog signal definition, zero, or range
• Controlling an auxiliary pressure channel
• Changing polarity of a thermal conductivity detector
(TCD)
• Turning the hydrogen flow to a nitrogen- phosphorus
detector (NPD) on or off
• Switching digital signal output (requires an Agilent data
system)
• Pausing ("freezing") and resuming digital signal output
(requires an Agilent data system)
The changes are entered into a run table that specifies the
setpoint to be changed, the time for the change, and the new
value. At the end of the chromatographic run, most setpoints
changed by a run time table are returned to their original
values.
Valves can be run time programmed but are not restored to
their starting position at the end of the run. You must
program the reset operation in the run table if this action is
desired. See "From the run or clock time tables"
page 221.
The [Run Table] key is used to program the following timed
events.
• Valves (1- 8)
• Multiposition valve
• Signal type (see "Signal Types"
• Analog signal definition, zero, and range
• Auxiliary pressures (1 through 9)
• TCD negative polarity (on/off)
on
on page 227)
Advanced Operation Manual