Leybold vacuum PhoeniXL300, Техническое руководство

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GA10.218_1.01 - 11/2004 ⏐
67
Since the effective pumping rates are usually not known due to tje con-
ductances of the vacuum connections, we recommend the following indi-
rect measurement:
1. Set up the Phoenix for operation
2. First an internal calibration must be performed with machine factor = 1
(Refer to chapter 7)
3. Connect an external calibrated leak (for example) 2.0x10
-6
mbarl s
-1
to
the test chamber
4. Measure leak rate of the external test leak, for example
5.0x10
-8
mbarl s
-1
5. The machine factor is the quotient of the desired value and the actual
value. Desired value: 2.0x10
-6
mbarl s
-1
/ 5.0x10
-8
mbarl s
-1
= machine
factor 40
6. Set the acquired value in the menu point
7. Calibrate again internally so that the machine factor is taken
8. All signals that are measured in further runs are multiplied by factor 40
and then shown in the display
6.6.1.6 Leak rate internal test leak
• Main Menu > Settings > Vacuum settings > Leak rate internal test leak
The value of the internal test leak can be set. See Chapter 4.1.2.7 Numeri-
cal Entries for the description of the entry.
Normally there is no reason to edit the leak rate of the internal test leak
besides after a change or a recalibration of the internal test leak. A wrong
leak rate of the internal test leak will lead to wrong leak rate readings!
6.6.2 Filter and background
• Main Menu > Settings > Filter and background
The hint of leak rate filters and background condition can be chosen. The
default setting for the leak rate filter is auto.
Softkey 2: Calculate inlet area background
This function is for assignation of the background in the inlet area
Softkey 3: Background suppression
Setting of the internal condition for the background
Softkey 7: Leak rate filter
The hint of leak rate filters can be chosen