Process Variable Calculations; Percent Oxygen; Percent Carbon; Dewpoint - Marathon OXYMITH TRANSMITTER F200060 Operator's Manual

Process Variable Calculations

The transmitter has a selectable process calculation for percent carbon, percent oxygen, or
dewpoint. The following equations are used to derive these values;

Percent Oxygen

Where: E = probe millivolts, Tk = probe temperature in degrees Kelvin.
The 20.95 is the %O2 in air.

Percent Carbon

%C = 5.102 ---------------------------------------------------
Where: E = probe millivolts, Tk = probe temperature in Kelvin, and PF is the process
factor.

Dewpoint

DP = -------------------------------------------------------------------- - 459.69
6.281216 + log((29*PF+400)+(E-1267.8)/(0.05512*Tr)
Where: E = probe millivolts, Tr = probe temperature in Rankin, PF is the process factor,
and DP is the dewpoint in Fahrenheit.
11/14/2006
20.95
%O2 = -----------------------
e (E/0.0215*Tk)
e ((E-786)/(0.043102*Tk))
(29*PF + 400)+
4238.7
Page 8 of 23
e ((E-786)/(0.043102*Tk))
Rev. 14