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7-5. HCV and OCV setup
This is the function that selects ratio between hydrogen and carbon (Hcv) and ratio between oxygen
and carbon (Ocv) for the fuel. This function is used to calculate Lambda value which is defined by the
ratio of actual AFR and theoretical AFR through Brettschneider formula. Following table is for normal
Hcv and Ocv, but there are cases to apply other values depending on formulation of fuels and country
to use. Once Hcv and Ocv values are setup, they are stored in memory and are maintained even after
rebooting.
①
Press MENU key four times from standby mode.
CO
HC
%
ppm
CO
2
O
2
%
%
Lambda
AFR
NO
X
The value of Hcv and Ocv is not possible to change. If it requires to change the value of Hcv and
Ocv due to the difference of molecular structure of the fuel, please contact those whom you
purchased the analyzer from.
Gasoline
LPG
CNG
Alcohol
Hcv
1.8500
2.5000
3.830
3.000
Ocv
0.0000
0.0000
0.000
0.5000
AFR
14.7
15.5
16.9
9.0
Random change of Hcv and Ocv can distort air surplus rate and AFR.
So maintain the values in the following table.
However, in case fuel composition differs and you require to change it
temporarily, note that you have to enter a precise value. If not so, this
analyzer may display any error value of Lambda(air surplus rate) and AFR.
CAUTION
!