Article 24 5.

An engine that is representative of the engine type or, where applicable, of the parent engine of the engine family, or an engine selected in accordance with the second subparagraph of paragraph 3, shall be tested on a dynamometer using the applicable non-road steady-state test cycle identified in Tables IV-1 to IV-10 of Annex IV. The manufacturer may choose whether to conduct that test using the discrete-mode or the ramped-modal test method. Except in the cases referred to in paragraphs 7 and 8, a variable-speed engine of a particular category used in a constant-speed operation of the same category need not be tested using the applicable constant-speed steady-state test cycle.