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AO2000
CONTINUOUS GAS ANALYZERS | OI/AO2000-EN REV. B
239
Test gases
Zero-point calibration
Quality
Nitrogen, Quality 5.0, synthetic air or catalytically cleaned
air with an organic C content < 1 % of span
Inlet pressure
p
e
= 1000 ± 100 hPa
Flow
130 to 250 l/h
End-point calibration
Quality
Sample component or substitute gas component in ni-
trogen or synthetic air with concentration adjusted to the
measuring range
Inlet pressure
p
e
= 1000 ± 100 hPa
Flow
130 to 250 l/h
Zero offset
If the zero reference gas is not completely free of hydrocarbons (even puri-
fied nitrogen contains fractions of hydrocarbons), negative measured values
may be displayed in small measuring ranges (the process gas is "cleaner"
than the zero reference gas).
Test gas infeed
The test gases for the zero and span calibration must be fed in via solenoid
valves; the test gases are connected automatically by means of the integral
valves.
If the test gas is connected at the sample gas inlet the zero gas and span
inlet gas must be sealed.