274  AO2000 CONTINUOUS GAS ANALYZERS  |  OI/AO2000-EN REV. B 
 
 
 
Basic calibration 
What does the basic calibration do? 
A basic calibration of an analyzer module sets the module back in an initial 
state. The offset drift and amplification drift are set to zero. The drift history 
is lost. 
When should a basic calibration be performed? 
Basic calibration of an analyzer module should be performed only in excep-
tional cases when changes that affect calibration have been made. This may 
be the case e.g. after exchanging subassemblies.   
For the Uras26 analyzer module, a basic calibration can be performed at the 
zero point for calibration to the cooler dew point during commissioning at 
the sampling point.   
Check prior to a basic calibration 
Prior to a basic calibration, check and ensure 
•  That the gas analyzer is in proper operating condition 
•  That the sample conditioning units are in proper operating condition 
•  That the correct test gases are being used. 
Test gases 
The zero and/or span calibration test gases are required for a basic calibra-
tion. 
Performing the basic calibration 
The basic calibration is performed for each sample component or – for the 
Caldos25 and Magnos27 analyzer modules – for each measurement range. 
The basic calibration can be performed 
•  Individually at the zero point 
•  Individually at the end point, as well as 
•  Together (successively) at the zero and end points. 
A calibration reset (see page 273) is also performed in the case of common 
basic calibration at the zero and end points.   
Menu path 
MENU → Maintenance/Test → Analyzer spec. adjustm. → 
Basic Calibration