External Sniff Calibration Setup - Agilent Technologies G8610A Operation Manual

5. Place system into Test and ensure the test port pressure adjusted between 5E-1 Torr 1
Torr (750 mTorr preferred).
6. Perform an internal calibration.
7. Perform an external calibration using the sniffing probe (Figure 5-18) by:
a. Selecting Calibration > Calibrate With > External Leak.
b. Entering the value of the external calibrated leak. Keep the probe at the inlet of the
standard leak.
c. Pressing Calibrate. The system performs an instant calibration in 2 seconds.
8. Select Test Configurations > Applications Setup.
9. Select PPM Sniff Method > Application Setup.
10. Select the MFM option.
11. .Select Serial Port - This establishes RS232 communication between the MFM and the
leak detector.
The leak detector is now ready to measure the concentration of Helium in PPM.
5.1.3.10.5 Mass Flow Meter Setup Configuration
Figure 5-19 depicts the connection required to use the Alicat mass flow meter in a test
setting. This setup connects from the leak detector test port to the fine metering valve
assembly, to the mass flow meter (fitted on both ends with 1/4" NPT NW25 fitting (Agilent
part number KAMP250250S), to the hose. This series is important to be fitted in this order to
ensure optimal helium response time. Instead of this setup using the purchased metering
valve, the operator may choose to use the setup outlined in Figure 5-20, though that
configuration can be awkward to hold as a probe. The mass flow meter must be kept above
a metering valve, whether the sniffer probe, or the fine metering valve described. This keeps
the mass flow meter close to atmospheric pressure, ensuring maximum accuracy.
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Agilent Technologies Helium Leak Detector
Figure 5-18 External Sniff Calibration Setup
The Calibration button on the PPM Sniff application is only to
NOTE
calibrate using a known PPM mixture.