Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:16:p99
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 16 (pt 99/108)
Character Range: 1169208–1171993

requirements to document the insulation materials may be waived.

              2.1.1.  If active heat storage devices are installed, only vehicles that meet the following requirements shall be considered to be part of the same ATCT Family:

                  (a) The heat capacity, defined by the enthalpy stored in the system, is within a range of 0 to 10 per cent above the enthalpy of the test vehicle; and

                  (b) The OEM can provide evidence to the technical service that the time for heat release at engine start within a family is within a range of 0 to 10 per cent below the time for the heat release of the test vehicle.

              2.1.2. Only vehicles that meet the criteria set out in paragraph 3.9.4. of this Annex B6a shall be considered to be part of the same ATCT Family.

              3. ATCT Procedure

              The Type 1 test specified in Annex B6 shall be carried out with the exception of the requirements specified in paragraphs 3.1. to 3.9. of this Annex B6a. That requires also a new calculation and application of gearshift points in accordance with Annex B2 taking into account the different road load as specified in paragraph 3.4. of this Annex B6a.

              3.1. Ambient conditions for ATCT

              3.1.1. The temperature (Treg) at which the vehicle should be soaked and tested for the ATCT shall be 14 °C.

              3.1.2. The minimum soaking time (tsoak_ATCT) for the ATCT shall be 9 hours.

              3.2. Test cell and soak area

              3.2.1. Test cell

              3.2.1.1. The test cell shall have a temperature set point equal to Treg. The actual temperature value shall be within ± 3 °C at the start of the test and within ± 5 °C during the test.

              3.2.1.2. The specific humidity (H) of either the air in the test cell or the intake air of the engine shall be such that:

              3.0 ≤ H ≤ 8.1  (g H2O/kg dry air)

              3.2.1.3. The air temperature and humidity shall be measured at the cooling fan outlet at a rate of 0.1 Hz.

              3.2.2. Soak area

              3.2.2.1. The soak area shall have a temperature set point equal to Treg and the actual temperature value shall be within ± 3 °C on a 5 minute running arithmetic average and shall not show a systematic deviation from the set point. The temperature shall be measured continuously at a minimum frequency of 0.033 Hz.

              3.2.2.2. The location of the temperature sensor for the soak area shall be representative to measure the ambient temperature around the vehicle and shall be checked by the technical service.

              The sensor shall be at least 10 cm away from the wall of the soak area and shall be shielded from direct air flow.

              The air-flow conditions