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Transpector MPH Operating Manual
6.6.1.2 Selecting Tune Masses
The most important portion of mass scale tuning is determining which masses are
to be tuned.
Transpector MPH has two different calibration standards available as options.
If Transpector MPH has the CPM Test Mixture Calibration Reference installed,
continue to
section 6.6.1.2.1, Selecting Masses for Tuning with a CPM Test
Mixture Calibration Reference, on page 6-16
.
If Transpector MPH has the Argon Standard Calibration Reference installed,
continue to
section 6.6.1.2.2, Selecting Masses for Tuning with an Argon
Standard Calibration Reference, on page 6-17
.
If Transpector MPH does not have an optional calibration standard, there are three
different methods of tuning.
To tune using a user-supplied test mixture, continue to
Selecting Masses for Tuning with a User-Supplied Test Mix, on page 6-17
To tune using process gases, continue to
section 6.6.1.2.4, Selecting Masses
for Tuning with Process Gases, on page 6-17
To tune with background gases, continue to
section 6.6.1.2.5, Tuning with
Background Gases, on page 6-18
.
6.6.1.2.1 Selecting Masses for Tuning with a CPM Test Mixture Calibration Reference
The optional CPM Test Mixture Calibration Reference is a calibrated leak-rate that
consists of the chemical species shown in
.
100 AMU sensors use masses 2, 4, 28 and 86 for tuning
200 AMU sensors use masses 2, 4, 28, 86 and 134 for tuning
300 AMU sensors cannot be fully tuned with the CPM Test Mixture
NOTE:
Use the 200 AMU sensor masses for tuning from 1-200 AMU.
Another calibration reference will be required to tune the
200-300 AMU mass range.
Table 6-4 CPM Test Mixture Composition
Gas Specie
Tune Mass
hydrogen (1%)
2
helium (1%)
4
nitrogen (1%)
28
argon (balance)
N/A
krypton
86
xenon
134