Teledyne BDS-3000 - Oxygen analyzer - Manual (Page 59)

Oxygen Analyzer Operation
Teledyne Analytical Instruments 45
4.3.8 Negative Value Display
The operator is able to set the display not to show negative
readings. To access this option, Press the SYSTEM key and access the
second screen of the System menu:
Version Diag Xout
Neg-N Filter-5 More
By using the Left or Right keys, the Neg- field can be accessed.
Once that field is selected, use the Up or Down keys to toggle from N to
Y or Y to N . Setting to N means that when the reading of the sensor
drifts negative, the display will stay at zero. To follow negative upsets,
set this field to
Y . The default setting is N .
4.3.9 The Gas Correction Factor
When the background gas is changed. this function can adjust the
calibration of the instrument to compensate for the sensor change of
output. This is helpful when the gas background needs to be changed
and only a calibration bottle with nitrogen background is used. The
default setting is 1.00, for nitrogen gas background. To set this factor,
press the System key and access the third screen:
GasBkgnd TempComp
Trbsht temp: 21.0 o C
Select GasBkgnd and press the ENTER key to see the function
screen:
Gas Background
Correction: 1.00
Use the Up or Down keys to adjust the value. The working range is
0.25 to 2.50. This factor will divide the output. For example if the factor
is set to 2.00, the output of the sensor, when read by the electronics will
be divided by two.
Special consideration on the working range: Changing the gas
correction factor has an effect on the maximum working range of the
analyzer, e.g.: if a gas factor of 2.00 is selected the maximum working
range of the analyzer is 50 ppm. Any reading above this, may saturate
the amplifier. The automatic sensor shutdown function will become