58
Installation, Operation and Maintenance Manual
OXYvisor Optical Oxygen Analyzer
T
actual
= Temperature customer knows to be correct
T
measured
= Temperature from RTD
T
last
= Corrected temperature (T
actual
) from last calibration. Default is 25°C for first time calibration.
If T
actual
- T
measured
< 15°C then the difference between the two temperatures is applied across the entire
temperature measurement range of -15 to 100°C (5 to 212°F). Additionally, T
last
should be stored as the last
reference point for the temperature calibration.
If T
actual
- T
last
≥ 15C then the calibration line should be redrawn (see in green above). The slope of this line
can be determined by the two temperature values. Graphically it is shown to the below.
Ambient Pressure Sensor Calibration
It is normally not necessary to calibrate the ambient pressure sensor. However, if there is an offset the ambient
pressure sensor can be calibrated via a Smart Calibration routine. The routine allows for either a 1-point offset
adjustment or a 2-point offset and slope adjustment.
The analyzer always performs an offset unless a successive calibration is performed with a <250 mBar
differential from the first and then is automatically adjust the slope. Details of the calibration logic are shown:
5.12.7 - Calibration - Pressure Sensor Calibration
P
actual
= Pressure customer knows to be correct
P
measured
= Pressure from Atmospheric Pressure Sensor on circuit board
P
last
= Corrected pressure (P
actual
) from last calibration. Default is 1013 mbar for first time calibration.
If P
actual
- P
measured
< 250 mBar then the difference between the two pressures is applied across the entire
pressure measurement range of 500 to 2000 mbar. Additionally, P
last
should be stored as the last reference
point for the Pressure calibration.
If P
actual
- P
last
≥ 250 mbar then the calibration line should be redrawn (see in green above). The slope of this
line can be determined by the two pressure values. Graphically it is shown above.
Figure 32 - Temperature Sensor - Smart Calibration
Figure 33 - Pressure Sensor - Smart Calibration
Calibration