This part specifies two test methods for hydraulic motors. Describes two comparable methods of measurement, namely the constant torque method and the constant pressure method. The accuracy of measurements is divided into 3 classes, A, B, and C which are explained in the normative annex A. The normative annex B includes the classes of measurement accuracy, and the normative annex C contains the use of practical units. This second edition cancels and replaces the first edition (1988).