Leak rate internal test leak, Machine factor, Auto leak test adjustments – INFICON UL1000 Helium leak detector User Manual
Page 69: Leak rate internal test leak machine factor, Warning
Description of the Menu
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6.6.1.4
Leak rate internal test leak
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The value of the internal test leak can be set. See Chapter
for the description of the entry.
6.6.1.5
Machine factor
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The machine factor takes into account that an additional external pump set is used.
Based on an internal calibration only, all measured leak rate would be measured too
small. The measured leak rate is multiplied with the machine factor and the result is
displayed. This factor is only used for vacuum measurement modes (not for sniff
mode). See Chapter
for the description of the entry.
The machine factor can be estimated by taking into consideration the Helium
absorbing capability of the UL1000 and UL1000 Fab and the external pump.
Exactly, this is the result of the measured leak rate of an external test leak on the test
sample once with and then without the external pump. The difference between the
two results is the machine factor.
Adjust the machine factor to the value 400 when using the helium sniffer QUICK
TEST.
The machine factor can be used to correct the leak rate indication to an air equivalent
reading. By using this setting the display reads the leak rate equivalent to air. (The
machine factor for this correction is 3,7 x 10E-1 ). When using this setting the status
is indicated on the display by COR.
To return to standard indication of the leak rate, use the default settings (machine
factor is 1.0).
6.6.1.6
Auto Leak Test adjustments
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Menu >Settings >Vacuum Settings > Auto Leak Test settings
All parameters for a test at hermetic sealed parts can be setted.
Measurement period
The Measurement period can be setted between a Minimum and a Maximum value
(see
Warning
Normally there is no reason to edit the leak rate of the internal test leak besides after
a change of the internal test leak. A wrong leak rate of the internal test leak will lead
to wrong leak rate readings!