Infrared Gas Analyzer Appendix
Teledyne Analytical Instruments 115
A.3 Optional Functions
O
2 correction: Correction of measured NO, SO2 and CO

gas concentrations into values at reference

O2 concentration

Correction formula: Cs
Os-21
On-21
C×=
C: Sample gas concentration after O2
correction
Cs: Measured concentration of sample gas
Os: Measured O2 concentration (Limit setting:
1 to 20% O2)
On: Reference O2 concentration (value
changeable by setting. 0 to 19% O2)
Average value after O2 correction and O2 average value calculation:
The result of O2 correction or instanta-
neous O2 value can be output as an av-
erage value in the preset period of time.
The moving average method is used for
averaging in which sampling is carried out
at intervals of 30 seconds.
Output is updated every 30 seconds. It is
the average value in the determined period
of time just before the latest update.
Averaging time is settable within 1 to 59
minutes (in increments of 1 minute) or 1
to 4 hours (in increments of 1 hour).
Average value resetting: The above-mentioned output of average
value is started from the initial state by
opening the average value resetting input
terminals after short-circuiting for 1.5 sec-
onds or longer.
Output is reset by short-circuiting and re-
started by opening