Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p93
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 93/150)
Character Range: 985407–988389

at the specified atmospheric pressure:

                T = -0.4514 x (101.3 – pb) + 311      (5)

                Where:

                T is the ambient air temperature, K

                pb is the atmospheric pressure, kPa
                  (c) All engine coolant temperature above 343 K (70 °C).
               The applicable ambient atmospheric pressure and temperature conditions are shown in Figure 1.
               WNTE Atmospheric Pressure and Temperature Range
           Figure 1
           Illustration of atmospheric pressure and temperature conditions
7.  Off-cycle laboratory testing and vehicle testing of engines at type approval
The off-cycle laboratory test requirements shall not apply for the type approval of positive ignition engine under this Regulation.
7.1. World-harmonized Not-To-Exceed control area
 The WNTE control area consists of the engine speed and load points defined in paragraphs 7.1.1. through 7.1.6. Figure 2 is an example illustration of the WNTE control area.
7.1.1. Engine speed range
 The WNTE control area shall include all operating speeds between the 30th percentile cumulative speed distribution over the WHTC test cycle, including idle, (n30) and the highest speed where 70 per cent of the maximum power occurs (nhi). Figure 3 is an example of the WNTE cumulative speed frequency distribution for a specific engine.
7.1.2. Engine torque range
 The WNTE control area shall include all engine load points with a torque value greater than or equal to 30 per cent of the maximum torque value produced by the engine.
7.1.3. Engine power range
 Notwithstanding the provisions of paragraphs 7.1.1. and 7.1.2., speed and load points below 30 per cent of the maximum power value produced by the engine shall be excluded from the WNTE control area for all emissions.
       7.1.4.  Application of engine family concept
 In principal, any engine within a family with a unique torque/power curve will have its individual WNTE control area. For in-use testing, the individual WNTE control area of the respective engine shall apply. For type approval (certification) testing under the engine family concept of the WHDC gtr the manufacturer may optionally apply a single WNTE control area for the engine family under the following provisions:
                  (a) A single engine speed range of the WNTE control area may be used; if the measured engine speeds n30 and nhi are within ±3 per cent of the engine speeds as declared by the manufacturer. If the tolerance is exceeded for any of the engine speeds, the measured engine speeds shall be used for determining the WNTE control area;
                  (b) A single engine torque/power range of the WNTE control area may be used, if it covers the full range from the highest to the lowest rating of the family. Alternatively, grouping of engine ratings into different WNTE control areas is permitted.
       Figure 2
       Example of WNTE control area
       Figure 3
       Example of WNTE