Agilent Technologies PHD-4 User Manual page 83

Trouble
Sensitivity test fault
Trouble
Sensor test fault
PHD-4 Portable Helium Detector User Manual
Technical Information
Answer
Due to difficulties in sensor trigger (sensor too clean)
Spray few He near the probe during “Self test”
1.
procedure
Answer
Due to saturation of the sensor (High ion current) or large
amount of He trapped in the capillary quartz.
Provide N2 or air free of He
1.
Repeat many times “Self-test” procedure.
2.
As a general rule
Avoid sniffing large amount of He
(concentration, pressure)
Use backflow valve protection
Start checking in LS
/ 87-900-120-01 (F )
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Troubleshooting
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