Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:1714:p11
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 1714 (pt 11/15)
Character Range: 717798–720940

be spaced equally but all data sets shall be reported.
                  The data sets and the values Prated and nrated shall be taken from the power curve as declared by the manufacturer.
                  The full load power at engine speeds not covered by UN Regulation No. 85 shall be determined according to the method described in UN Regulation No. 85;
              (i) Determination of ngvmax and vmax
                  ngvmax, the gear in which the maximum vehicle speed is reached and shall be determined as follows:
                  If vmax(ng) ≥ vmax(ng-1) and vmax(ng-1) ≥ vmax(ng-2), then:
                  ngvmax = ng and vmax = vmax(ng).
                  If vmax(ng) < vmax(ng-1) and vmax(ng-1) ≥ vmax(ng-2), then:
                  ngvmax = ng-1 and vmax = vmax(ng-1),
                  otherwise, ngvmax = ng -2 and vmax = vmax(ng-2)
                  where:
                         vmax(ng)  is the vehicle speed at which the required road load power equals the available power Pwot in gear ng (see Figure A2/1a).
                         vmax(ng-1)  is the vehicle speed at which the required road load power equals the available power Pwot in the next lower gear (gear ng-1). See Figure A2/1b.
                         vmax(ng-2)  is the vehicle speed at which the required road load power equals the available power Pwot in the gear ng-2.
                  Vehicle speed values rounded according to paragraph 6.1.8. of this Regulation to one place of decimal shall be used for the determination of vmax and ngvmax.
                  The required road load power, kW, shall be calculated using the following equation:
                  where:
                  v  is the vehicle speed specified above, km/h.
                  The available power at vehicle speed vmax in gear ng, gear ng - 1 or gear ng-2 shall be determined from the full load power curve, Pwot(n), by using the following equations:
                  nng = (n/v)ng × vmax(ng);
                  nng-1 = (n/v)ng-1 × vmax(ng-1);
                  nng-2 = (n/v)ng-2 × vmax(ng-2),
                  and by reducing the power values of the full load power curve by 10 per cent.
                  The method described above shall be extended to even lower gears, i.e. ng- 3, ng-4, etc. if necessary.
                  If, for the purpose of limiting maximum vehicle speed, the maximum engine speed is limited to nlim which is lower than the engine speed corresponding to the intersection of the road load power curve and the available power curve, then:
                  ngvmax = ng and vmax = nlim / (n/v)(ng).
Figure A2/1a
An example where ngvmax is the highest gear
Figure A2/1b
An example where ngvmax is the 2nd highest gear
                  (j) Exclusion of a crawler gear
                  Gear 1 may be excluded at the request of the manufacturer if all of the following conditions are fulfilled:
                     (1)  The vehicle family is homologated to tow a trailer;
                     (2) (n/v)1 × (vmax / n95_high) > 6.74;
                     (3) (n/v)2 × (vmax / n95_high) > 3.85;
                     (4) The vehicle, having a mass