User`s guide

Operation
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being chromatographed. This setting is intended to ensure
that the current run has finished in time for the trap
desorption of the next sample.
NOTE: Laboratory temperatures can strongly influence the GC
oven cool-down time and can vary (for example,
overnight). The GC cycle time setting should take into
account the longest oven cool-down time expected during
the analytical sequence.
The ATD will use this value to calculate when to load the next
tube. If you are running an ATD, the cycle time will be used to
determine at which time the next tube should be loaded in order
to run tubes successively without wasted time in between
samples.
In this case the ATD will not wait for a GC Ready signal before
it begins to desorb the tube. Once, the trap is ready for
desorption, the ATD waits for the GC Ready signal. You must
set this time accurately as your sample will be retained on the
trap until the GC becomes ready.
Relays—This dialog box provides access to the timed events for
the relays on the Options board. See Timed Events on page 183
for details on connecting remote accessories and programming
the On and Off times.
Standard Inject Time—If your ATD/TD is equipped with the
Internal Standard Addition accessory, a gaseous internal standard
can automatically be introduced onto every sample tube prior to
desorption. The standard will be added after the tube purge.
The Internal Standard (IS) valve is activated for the duration of the
Standard Injection time to allow the introduction of a volume of
standard onto the sample tube. After the end of the standard injection
time, the IS valve is closed and the ATD/TD will proceed with
desorption of the tube