A further validation point was the variation of the test cell temperature during the tests. The class 3 cycle was used for the evaluation. Figure 6 shows the time history of the test cell temperature with the lowest variation, Figure 7 shows the case with the highest variation.
The variation ranges for all tests are shown in Figure 8.
Based on these results the following requirements were drafted for the GTR:
The test cell shall have a temperature set point of 296 K. The tolerance of the actual value shall be within ± 5 K. The air temperature and humidity shall be measured at the vehicle cooling fan outlet at a rate of 1 Hz.
Figure 6: Best case of test cell temperature over all 4 phases of the class 3 WLTC
