LEYBOLD 250000, Руководство по эксплуатации

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Head
GA10218_0101 - 5/2002 ⏐
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Since the effective pumping rates are usually not known due to the con-
ductances of the vacuum connections, we recommend the following indi-
rect measurement:
1. Set up the PhoeniXL 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 2.0·10
-6
mbar l/s) to
the test chamber
4. Measure leak rate of the external test leak, for example
5.0·10
-8
mbar l/ s
5. The machine factor is the quotient of the desired value and the actual
value. Desired value: 2.0·10
-6
mbar l/ s / 5.0·10
-8
mbar l/ s = machine
factor 40
6. Set the acquired value in the menu point
7. Calibrate again internally so that the machine factor is taken over
8. All signals that are measured in further measurements are multiplied by
factor 40 and then shown in the display
6.6.1.7 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 recertification 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 & Background
Main Menu > Settings > Filter & Background
The type 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. See
chapter 6.6.2.1
Softkey 3: Background suppression
Setting of the internal condition for the background. See chapter 6.6.2.2
Softkey 7: Leak rate filter
The type of leak rate filter can be chosen. See chapter 6.6.2.3