Teledyne Max-5 - Combustion efficiency analyzer - Manual (Page 9)

methane in nitrogen. In other cases, a hydrogen and carbon monoxide mixture might be used. In
the presence of catalyst poisons, the combustibles sensor will hold its sensitivity to a
hydrogen/CO mixture far longer than to methane; therefore, it is important to calibrate it with the
right mixture.
TEMPERATURE AND CALCULATED VALUES
Temperature. The MAX 5 uses a type “K” thermocouple. The temperature section includes
circuitry and software to linearize the thermocouple signal and provide a zero-point reference.
The temperature display reads in degrees Centigrade or degrees Fahrenheit depending on which
temperature you select.
Carbon Dioxide. Because carbon dioxide is a combustion product, and its concentration level at
any given time depends on how completely a given fuel is burned and its by-product of carbon
monoxide is oxidized, the computer is able to calculate the carbon dioxide level. The oxygen
and combustibles section readings and the fuel type you selected at the front panel are factors in
the calculation resulting in the carbon dioxide concentration on a dry basis.
*U.S. Patent No. 4,477,403; U.K. Patent No. GB21405S6B; France Patent No. 2546626.
Efficiency. The computer calculates the efficiency level. The reading, calculated from the
temperature and oxygen readings and the type of fuel selected, is not absolute; rather, it is a
relative indication of the degree of improvement achieved by adjusting the burner. The
efficiency is based on British Standards recommendations and is calculated from this formula:
Efficiency = 100--K3 -- _____K1 x T_____
K2 x (1 - O
2
)
21
Where:
T = net temperature
°C
O
2
= oxygen concentration %
K1 = fuel factor on hydrocarbon composition
K2 = theoretical maximum CO
2
concentration of flue gas
K3 = correction factor for latent heat (“wet” losses)
The values of K1, 2 and K3 for the four fuels covered by the MAX 5 are:
K1 K2 K3
Natural
Gas 0.38 11.8 11.0
#2 oil 0.56 15.6 6.0
#6 oil 0.6 15.9 5.0
Coal 0.63 18.6 3.0
SAMPLING SYSTEM DESCRIPTION