# Commission Regulation (EU) 2017/1151 of 1 June 2017 supplementing Regulation (EC) No 715/2007 of the European Parliament and of the Council on type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information, amending Directive 2007/46/EC of the European Parliament and of the Council, Commission Regulation (EC) No 692/2008 and Commission Regulation (EU) No 1230/2012 and repealing Commission Regulation (EC) No 692/2008 (Text with EEA relevance), Division 8.2.1: Downscaling procedure for Class 1 vehicles


Figure A1/14 shows a downscaled medium speed phase of the Class 1 WLTC as an example.
Figure A1/14
Downscaled medium speed phase of the class 1 WLTC
For the Class 1 cycle, the downscaling period is the time period between second 651 and second 906. Within this time period, the acceleration for the original cycle shall be calculated using the following equation:
aorigi=vi+ 1− vi3,6where:
viis the vehicle speed, km/h;
iis the time between second 651 and second 906.
The downscaling shall be applied first in the time period between second 651 and second 848. The downscaled speed trace shall be subsequently calculated using the following equation:
vdsci+ 1=vdsci+ aorigi×1− fdsc× 3,6with i = 651 to 847.
For i = 651, vdsci=vorigi
In order to meet the original vehicle speed at second 907, a correction factor for the deceleration shall be calculated using the following equation:
fcorr_dec=vdsc_848− 36,7vorig_848− 36,7where 36,7 km/h is the original vehicle speed at second 907.
The downscaled vehicle speed between second 849 and second 906 shall be subsequently calculated using the following equation:
vdsci=vdsci− 1+ aorigi− 1× fcorr_dec× 3,6for i = 849 to 906.

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Source: https://www.legislation.gov.uk/eur/2017/1151/annex/Sub/1/division/division/8./division/8.2./division/8.2.1. (the official version)
Page: https://openlegislation.uk/eu-regulation-2017-1151/annex-Sub/1/division/division-8./division-8.2./division-8.2.1.
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.