Pfeiffer Vacuum PrismaPro QMA 250 F1, Перевод оригинала

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Add or delete masses in or from the calibration table
Pfeiffer Vacuum has preset the masses 1, 2, 4, 28, and 86 in the default settings.
► Adjust the masses for the gas mixture with which you want to perform mass calibration by adding
and deleting masses.
► Do not delete the masses 1 and 2.
9.6.6 Calibrating with a test gas mixture
The ideal mixture includes the masses from the factory calibration for the respective mass range of the
PrismaPro to be calibrated.
Procedure
► Where applicable, use a test gas mixture from a gas supplier.
9.6.7 Calibration with process gases
Utilize process gas for mass calibration
1. Where applicable utilize the process gas to be analyzed for mass calibration.
2. Define typical masses that are important for process analysis for calibration.
Calibration with low mass
1. Do not calibrate the masses 1 u and 2 u (H) if hydrogen is not present in the process.
2. Do not delete hydrogen from the calibration table.
3. Calibrate the mass 4 u (He) if using the PrismaPro for leak testing.
4. Spray helium into a leak you have created.
– This provides the calibration for the low mass required.
Calibration with average mass
► If possible, use nitrogen (N) or another mass in this range, e.g., water (H
2
O), oxygen (O), etc. as
the average mass.
Calibration with higher mass
1. Calibrate with Argon (Ar) if the process does not contain any gases with masses > 40 u.
2. If the process contains higher masses, calibrate a mass between the average mass and 100 u for
analyzers with mass range of 100 u.
3. If the process contains higher masses, calibrate a mass between 100 u and 200 u for analyzers
with mass range of 200 u.
4. If the process contains higher masses, calibrate a further mass > 200 u for analyzers with mass
range of 300 u.
9.6.8 Calibration of the helium leak detection
Calibration with helium
1. Provide the helium required for calibration.
2. Route the helium into the vacuum chamber.
3. Calibrate the mass 4 u (He) for correct leak detection.
4. Calibrate the mass 4 u (He) if using the PrismaPro exclusively for leak testing.
Calibration with underground gases or with air
1. If you do not have any test gas mixtures or process gases available for the mass calibration, use
the residual gas in the vacuum chamber or feed in small quantities of ambient air to carry out the
mass calibration.
2. set the tune parameter to the default setting.
3. Delete all masses except for 1, 2 and 4 u from the calibration table.
4. Add masses 28, 40 or 44 u to the calibration table.
5. Calibrate the masses you added.
6. Delete the mass 4 u from the calibration table.
7. Calibrate the highest available mass in the system.
– In some cases, this may be the mass 40 or 44 u.
Maintenance
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