User`s guide

Operation
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Liquid N2 Option-Check this option to enable it on the Status
tab. The option allows you to cool the cold trap down to -100°C.
This option (L427-0009) must be installed on your instrument at
the factory or by a service engineer.
Number of Injections-This will record the total number of
injections since the last RESET.
Maintenance Alarm-Use this option to set the number of
samples to be performed until a warning message is displayed.
For example, after every 5,000 samples the o-ring seals in the
tube handling system may need to be replaced and this warning
can remind you of this action.Set the number according to your
application. If you encounter an unusually high number of leak
test faults, you may need to decrease the number of samples that
are run before the o-rings are replaced. You may also want to
check the cold trap at this interval.See Changing the Trap Filter
Disks on page 281 You can reset the counter by pressing the
Reset Counter button. You can check the number of injections
that have been made and adjust the maintenance interval at any
time.
Integrity Testing (only available in the TurboMatrix 650
ATD)—This test allows you to check pressure dropping across a
tube and/or trap.
Over time the packing in a tube can deteriorate and not be well
packed anymore. As shown in the following figure, the top trap
has deteriorated over time developed channels in the packing
material and has become charged. This deterioration will result
in inconsistent pressure readings. A well packed tube (or new
trap as shown in the bottom trap) will have a consistent reading
(or impedance). Different packing materials in the tube will
show different impedance values but these values will change as
the packing materials deteriorate over time. If you notice a
change in impedance values you should replace the tube and/or
trap.