Agilent Technologies Internal Filter (Kit of 5) For PHD 4 Portable Helium Leak Detector, SR03702959

The Agilent Technologies Internal Filter Kit is designed to be used with the PHD 4 Portable Helium Leak Detector.

The Agilent Varian PHD-4 Portable Helium Leak Detector permits fully automatic detection of concentrations of helium down to a lower limit of 2 parts for million (ppm). The value of the leak is shown in real time on the graphic display on the front panel. The instrument, which emits an acoustic signal proportional to the concentration of helium detected, incorporates a self-test program, making it possible to carry out any type of operation using the soft-keys on the front control panel. The operator can use the straps provided to carry the unit and locate leaks using the extensible probe.

The system to be tested is filled with a mixture of helium/air. The probe is passed over areas considered to be critical and, via a sampling pump, the mix of gases around the areas examined is sampled and piped towards the internal sensor. The sensor consists of a pressure detector and of a heated quartz capillary which is highly permeable to the molecules of helium, while permeability for all other atmospheric gases is negligible. While the atmospheric gases are vented to the outside, the molecules of helium reach the pressure detector. The electric signal proportional to the partial pressure of the helium taken from the detector, is processed by the microprocessor of the central unit. This permits direct readout of the concentration of helium on the display.