INFICON Sensistor ISH2000 Hydrogen Leak Detector - Manual (Page 29)

Hydrogen leak detector Sensistor ISH2000 - Operating Manual
OM-Sensistor ISH2000-EN-201304 29
EN
Audio Ready Pulse
This sets the standby sound to a silent or pulsating tone.
8.8 Measuring Mode Settings
In Measuring Mode the measured value is displayed in figures. The default unit is in
cc/s but it is possible to choose other units, See “Default parameters” on page 46.
To Measure Leaks
The Measuring 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 Measuring 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 suitable 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 Measuring mode the probe should be moved directly from a background
situation to the test point. The size of the leak in ppm, is shown on the display. The
probe can and should be removed from the measuring point as the measured value
remains on the display.
The period during which the measured value is displayed can be adjusted in the
Measuring Mode Settings menu.
Reject Level
Threshold level for Reject decisions. When this level has passed Reject it will be
indicated by audio and LED signals.
Note: The frequency of the acoustic signal in Measuring Mode is controlled by Reject
Level . A signal equal to the Reject Level will always give the same audio
frequency despite the actual signal strength.
Measuring Unit
The Custom Measuring Unit is the unit to be displayed during measurement.
The measured value will be automatically calculated for other flow units. For
example, if you calibrate with cc/s and want the instrument to show cc/min, the
displayed value is adjusted by a internal factor of 60.
If PPM or Custom units are selected there will not be an automatic conversion factor
calculation. If a unit conversion is needed, the conversion factor must be calculated
manually and inserted into the Correlation Value (under General Settings).
The Correlation Value is always set to 1 when the PPM or Custom units are selected,
but is adjustable afterwards.
The Measuring Unit is a text string with a maximum of 12 characters.
The following letters can be used; Upper and lower case English letters, the numbers
0 to 9, Е, Д, Ц, е, д, ц, %, /, and -. Space (““) is not supported. The string will be
shortened after the first space found.