346  AO2000 CONTINUOUS GAS ANALYZERS  |  OI/AO2000-EN REV. B 
 
 
 
Analyzer modules operating specifications 
Note on the metrological data of the analyzer modules 
The metrological data for the analyzer modules apply only when operated in 
conjunction with the central unit. They have been determined according to 
IEC 61207-1: 2010 "Expression of performance of gas analyzers – Part 1: Gen-
eral". They are based on nitrogen as the associated gas. Compliance with 
these data when measuring other gas mixtures can only be assured if their 
composition is known. The physical detection limit is the lower limit of the 
performance characteristics relative to the measuring range span. 
 
 
Caldos25: Operating specifications 
Linearity deviation  ≤ 2 % of span 
Repeatability  ≤ 1 % of span 
Zero drift  ≤ 1 % of span per week 
Sensitivity drift  ≤ 1 % of the measured value per week 
Output fluctuation (2 σ) 
≤ 0.5 % of smallest measurement range span at electronic T90 time = 0 s 
Detection limit (4 
σ) 
≤ 1 % of smallest measurement range span at electronic T90 time = 0 s 
Flow influence  ≤ 1 to 5 % of span at a flow change of ±10 l/h. At the same sample and test 
gas flow rate, the flow influence is automatically compensated. 
Associated gas effect  Knowledge of the sample gas composition is required for the analyzer con-
figuration. Measurement results can be greatly distorted by interfering 
components in complex (non-binary) gas mixtures. 
Temperature influence  At each point in the measurement range: ≤ 1 % of span per 10 °C, with re-
spect to the temperature during calibration. Thermostat temperature = 
60 °C; Ambient temperature in permissible range 
Air pressure effect  No effect in permissible operating condition range   
Power supply influence    24 V DC ± 5 %: ≤ 0.2% of span 
Position influence  < 1 % of span up to 10° deviation from horizontal orientation 
T
90
 time  T
90
 typical = 10 to 20 s; Option: T
90
 < 6 s (applies to a gas analyzer with 
one analyzer module)