ABB ACX Commissioning Instruction page 65

AO2000: Air Pressure Value Correction
When should the air
pressure value be set?
Limas21 and Uras26
with Integral Pressure
Sensor and Calibration
Cells
Air Pressure Value
Correction
Menu Path
CI/ACX-EN Rev. D
An incorrect air pressure value will produce erroneous measurement values.
The air pressure value must be checked and readjusted as required in the following
cases:
•
If the analyzer system's operating site altitude has changed since the last calibration
•
If the air pressure effect on the measured value is too high.
A pressure sensor is installed as standard equipment in the Limas21 and Uras26
analyzer modules. The pressure sensor is calibrated to 1013 hPa. This is the reference
pressure for the test gas concentration when measuring the calibration cells.
If the air pressure value needs to be changed, the following items are also required
•
Calibrate the sample components with test gases and then
•
Measure the calibration cells
The current atmospheric pressure can be entered as a correction value for each
analyzer module or for all analyzer modules as a group.
For one analyzer module:
→
MENU Maintenance/Test
Atm. press. anlz
For all analyzer modules as a group:
→
MENU Maintenance/Test
If the pressure sensor is connected to the sample gas output line, the sample gas flow
must be interrupted while calibrating the pressure sensor so that the sample gas
pressure does not distort the measured pressure.
ACX Analyzer System Commissioning Instruction
→
Analyzer spec. adjustm.
→
...
→
System
→
Atm. pressure
→
65