INFICON Sensistor ISH2000 Hydrogen Leak Detector - Manual (Page 9)

EN- 9 Sensistor ISH2000 Technical Reference Manual (TRM)
A 401
Hint: It is good practice to detect a leak, locate it, and immediately remove the
probe to avoid saturation. The probe is not damaged by the exposure but it will
recover more slowly. After excessive exposure it will be less sensitive for a short
period of time.
To Quantify Leaks
The Analysis Mode (or use the analysis figures in Combined Mode) is used for
measuring the size of a leak (or the concentration of a gas sample). To be able
to do this measurement and obtain correct values, the instrument must first be
calibrated using the calibration function.
In the Analysis Mode the detector determines the gas concentration from the
change, as the probe goes from being exposed to background to being
exposed to a certain gas concentration. The detector does not continuously
monitor the gas concentration but takes just one reading instead. Another suit-
able alternative name for this mode could be Sampling Mode. It is important to
keep this in mind when using the detector in this mode.
In Analysis Mode the probe should be moved directly from a background situa-
tion to the test point. The size of the leak in PPM, or any other selected units, is
shown on the display. The probe can and should be removed from the measur-
ing point as the measured value steadies and remains on the display. The period
during which the measured value is displayed can be adjusted in the Analysis
Mode Settings menu.