The purpose of this guide is to establish, in a general way, suitable procedures for commissioning a) non-reversible hydraulic machines without movable wicket-gates, i.e. storage pumps; b) reversible hydraulic machines with fixed blade impellers and without movable wicket-gates, operating as pumps; c) reversible hydraulic machines with fixed blade impellers and with movable wicket-gates, operating as pumps; d) reversible hydraulic machines with adjustable impeller blades and movable wicket-gates, operating as pumps. and associated equipment. This guide also indicates how such machines and equipment should be operated and maintained. This guide applies to storage pumps and reversible pump-turbines of all types, especially to large units coupled to electrical motor-generators. The guide excludes matters of purely commercial interest, except those inextricably bound up with the conduct of commissioning, operation and maintenance. It is understood that a document of this type will be binding only if, and to the extent that, both contract parties have agreed upon it. Wherever the guide specifies that documents, drawings or information are to be supplied by a manufacturer (or by manufacturers), each individual manufacturer shall be required to furnish the appropriate information for his own supply only. The guide is not concerned with water conduits, gates, valves, drainage pumps, cooling water equipment, generators, etc., except where they cannot be separated from the machine and its equipment. It is assumed that the turbine of the set or the pump-turbine operating as turbine has been commissioned beforehand in accordance with IEC Publication 545: Guide for Commissioning, Operation and Maintenance of Hydraulic Turbines, where applicable. Where this is not possible, an individual commissioning procedure shall be established at an early stage of plan design.