WLTP informal working group refinements to the amendment proposal.

Complete version of GTR No. 15 including the proposed Amendment 2 (GRPE/2017/7) and latest refinements by the WLTP informal group (GRPE-74-02). Amendment 2 corresponds to phase 2a development of the GTR, including the following modification to the text:

1. If an alternative value is applied for a parameter, such as a higher n_min_drive or an ASM, this parameter value has to be the same within an interpolation family (Paragraph 5.6.1.).
2. The mass in running order used for the calculation of the power to mass ratio is replaced by mass in running order minus 75 kg (paragraph 1. of Annex 1).
3. Idle engine speed n_idle is removed from the power curve measurement requirement (paragraph 2. of Annex 2).
4. The additional safety margin (ASM) value may be decided by manufacturer rather than the prescribed exponential curve (paragraph 3.4. of Annex 4).
5. The number of decimal place of road load coefficients is defined (paragraph 2.4. of Annex 4).
6. Additional restrictions are set to the application of the split run method for coastdown testing (paragraph 4.3.1.3.4. of Annex 4).
7. Specific data rejection criteria are added (paragraph 4.3.1.4.3. of Annex 4).
8. The “delta method” for road load determination is added (paragraph 6.8. of Annex 4 and other paragraphs. See section 4.4.25.for more detail).
9. The roller radius correction factor is modified(paragraph 6.6.3. of Annex 4).
10. The allowable combination of the test vehicle selection and family requirements are further clarified (paragraph 4.2.1.3. of Annex 4 and other paragraphs of Annex 4).
11. Provisions for an additional cooling fan are included(paragraph 1.1.5. and 1.1.6. of Annex 5).
12. The correction of measurement/recording frequency requirements are specified (over several annexes).
13. Calculation of the n/v ratio is defined (paragraph 8. of Annex 7).
14. The stepwise procedure for calculating the final test results of OVC-HEVs is added (paragraph 4.6. of Annex 8).

Official technical report detailing the rationale and decision-making behind the development of Amendment 2 (Development Phase 2a) of GTR No. 15.

The subject documents would permit Contracting Parties applying UN R83 and/or UN R101 and which have transposed GTR No. 15 (WLTP) into their local legislation to refuse to accept type approvals granted under the UN R83 and/or UN R101 as a compliance alternative to their national/regional legislation (i.e., aligned with GTR No. 15). OICA proposes to clarify the intent by deleting allusions to the measure as a form of derogation, to replace the phrase “may no longer accept” with “may refuse”, and to introduce a sunset clause to noting that the measure is intended as a stop-gap until such time as GTR No. 15 has been transposed into the corpus of UN Regulations.

European Commission report on the effort to transpose the GTR on light vehicle emissions into UN type approval regulations, including handling of current UN Regulations on emissions (notably, UN R83 and UN R101) and process for implementing the WLTP requirements.