LumaSense Technologies 3434i SF6 Leak Detector User Manual
Page 180
Chapter 13
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BE6028-14
3434i SF6 Leak Detector
LumaSense Technologies A/S
Page 180 of 191
WET MEAS. < DRY MEAS. FOR WATER FILTER and
HUMIDITY INTERFERENCE FACTOR < 0
Both these messages are associated with a combined zero-point and
humidity-interference calibration task.
WET MEAS. < DRY MEAS. FOR WATER FILTER
HUMIDITY INTERFERENCE FACTOR < 0
During the zero-point calibration task the signal is measured when
dry, zero gas is in the cell – this is a measure of the noise in the cell
when a particular optical filter is used. This measurement allows the
concentration offset factor for the particular filter to be calculated.
During the humidity-interference calibration task the signal in the cell
when a particular optical filter is used is measured when wet, zero gas
is in the cell – this signal is compared with the signal measured with
the water-vapour filter to give the humidity gain factor. The above
message is given if the humidity gain factor is found to be less than
zero. This could indicate that the zero-gas you used during the zero-
point calibration was not dry, or alternatively that the concentration of
water-vapour you used during the humidity-interference calibration
was too low.
GAS X: CALIBRATION FACTOR LESS THAN 0
This message is associated with a single-point span calibration task.
The gas conversion factor calculated during the single-point span
calibration task is found to be less than zero. This could indicate that
the concentration of gas used during the calibration was too low.
GAS X: LOW MEAS. > HIGH MEAS.
GAS X: MEAS. INDICATES LINEAR COHERENCE
GAS X: MEAS. DOES NOT FIT NON-LINEAR CURVE
GAS X: CALIBRATION IMPOSSIBLE: MAX ITER.
All these messages are associated with a two-point span calibration
task.
During a two-point span calibration the signal (V
high
) is measured
when the gas concentration C
high
is in the cell, and the signal (V
low
) is
measured when the gas concentration C
low