INFICON Sensistor ISH2000 Hydrogen Leak Detector - Manual (Page 59)

EN- 59 Sensistor ISH2000 Technical Reference Manual (TRM)
C 300
Irregular reference warning
The Detector will warn if the calibration signal is unreasonably high. This can
occur, for example, if 5% tracer gas mix has been used instead of proper refer-
ence gas or if the reference leak has an extra non-intentional leak. The warning
can be ignored and the calibration updated but the CAL_CONF output will not
be set.
Sensor condition indicator
The indicator bar extends in length when the sensor is detecting reference gas.
This indicator can be used for an early warning as to when a sensor replace-
ment will be needed.
The length of the bar shows the condition of the sensor. The bar will become
shorter if the sensor has lost some in sensitivity. The scaling of the indicator is
not precise enough to say at exactly what length the sensor must be replaced.
You will learn when this happens for your particular application. The instrument
will also tell you in clear text when sensitivity is too low.
Calibration messages
Message Explanation Remedy
Expose to background... Prepare the probe for
calibration by holding it
in hydrogen free
background. -
Detecting gas Gas signal is detected. Normal operation, gas
exposure can be
interrupted.
Repeat calibration Calibration was not
within 20% of last. Wait 30 s and calibrate
again.
Calibration OK Calibration was within
acceptable limit. Press Save (button 4) to
store calibration in
memory.
No gas or unstable signal. No gas signal or no stable
signal detected during
calibration. Check reference. Gas
valve may be shut.
Check that probe tip is
not clogged.
Signal when reference gas
is shut off. Happens for
reference gas only. Background is higher
than reference gas
concentration. Improve
ventilation.
Sensitivity too low for
Reject level Sensitivity of sensor is too
low to guarantee correct
response to a gas flow or
concentration equal to
the Reject level. The most
likely reason is that sen-
sor is too old. Check reference. Gas
valve may be shut.
Check that probe tip is
not clogged.
Check setting of Reject
Level.
Replace sensor if problem
remains.