Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p18
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 18/150)
Character Range: 764367–767402

and the engine fuel flow."

              A.1.3.2. Data consistency checks
A.1.3.2.1. Analysers and EFM data
The consistency of the data (exhaust mass flow measured by the EFM and gas concentrations) shall be verified using a correlation between the measured fuel flow from the ECU and the fuel flow calculated using the formula in paragraph 8.4.1.7. of Annex 4 to this Regulation. A linear regression shall be performed for the measured and calculated fuel rate values. The method of least squares shall be used, with the best fit equation having the form:
y = mx + b
Where:
y is the calculated fuel flow [g/s]
m is the slope of the regression line
x is the measured fuel flow [g/s]
b is the y intercept of the regression line
The slope (m) and the coefficient of determination (r²) shall be calculated for each regression line. It is recommended to perform this analysis in the range from 15 per cent of the maximum value to the maximum value and at a frequency greater or equal to 1 Hz. For a test to be considered valid, the following two criteria shall be evaluated:
       Table 2
       Tolerances
Slope of the regression line, m  0.9 to 1.1 - Recommended
Coefficient of determination     Min. 0.90 - Mandatory

              A.1.3.2.2. ECU torque data
              The consistency of the ECU torque data shall be verified by comparing the maximum ECU torque values at different engine speeds with the corresponding values on the official engine full load torque curve according to paragraph 5. of this annex.
              A.1.3.2.3. Brake-Specific Fuel Consumption
              The Brake Specific Fuel Consumption (BSFC) shall be checked using:
                  (a) The fuel consumption calculated from the emissions data (gas analyser concentrations and exhaust mass flow data), according to the formulae in paragraph 8.4.1.6. of Annex 4;
                  (b) The work calculated using the data from the ECU (Engine torque and engine speed).
              A.1.3.2.4. Odometer
              The distance indicated by the vehicle odometer shall be checked against the GPS data and verified.
              A.1.3.2.5. Ambient pressure
              The ambient pressure value shall be checked against the altitude indicated by the GPS data.
              A.1.3.3. Dry-Wet correction
              If the concentration is measured on a dry basis, it shall be converted to a wet basis according to the formula in paragraph 8.1. of Annex 4.
              A.1.3.4. NOx correction for humidity and temperature
              The NOx concentrations measured by the PEMS shall not be corrected for ambient air temperature and humidity.
              A.1.3.5. Calculation of the instantaneous gaseous emissions
              The mass emissions shall be determined as described in paragraph 8.4.2.3. of Annex 4.
              A.1.3.6. Calculation of the instantaneous PM number emissions

The instantaneous PM number (PNi) emissions (#/s) shall be determined by multiplying the instantaneous concentration of the PM number (#/cm3) with