Inficon 540-200, Перевод оригинальной инструкции по эксплуатации

Страница: 28 / 90

5 | Installation INFICON
28 / 90 T-Guard2_Operating-instructions-jina85en1-13-(2009)
5.2.2 Carrier gas measurement setup
Select the most helium-free environment possible for the measurement setup. For
reliable measurements with the T-Guard2, the helium content in the air must be less
than 10 ppm. By nature, air contains 5 ppm (0.0005%) helium.
1 2 3
4
5
6
7
8
9
Fig. 10: Measurement setup for carrier gas measurements
1 Carrier gas pump 6 Test object
2 Mass flow controller (optional) 7 Outside air inlet
3 Measurement line 8 Reference line
4 Measuring chamber 9 Fore pump
5 Fan
• Carrier gas pump
The carrier gas pump ensures carrier gas flow through the measurement
chamber. The following limits apply:
Expected leak rate Carrier gas flow
1 × 10
-5
mbar l/s <3000 sccm
1 × 10
-4
mbar l/s <30000 sccm
1 × 10
-3
mbar l/s <300000 sccm
• Mass flow controller (optional)
The mass flow controller controls the actual current mass flow. This allows for the
determination of a more accurate leak rate than an estimation of the mass flow.
• Measurement line