IEC 62006:2010 defines the test, the measuring methods and the contractual guarantee conditions for field acceptance tests of the generating machinery in small hydroelectric power installations. It applies to installations containing impulse or reaction turbines with unit power up to about 15 MW and reference diameter of about 3 m. The driven generator can be of synchronous or asynchronous type. This International Standard contains information about most of the tests required for acceptance of the hydraulic turbine such as safety approval tests, trial operating and reliability tests, as well for verification of cavitation, noise and vibration conditions, if required. This standard represents the typical methods used on smaller hydroelectric installations, and is divided into three classes as follows: Class A: Default, normal test program (panel measurement), to determine the maximum output of the installation. Class B: Recommended, extended test program, to determine the performance characteristics of the installation. Class C: Optional, comprehensive test program, to determine the absolute efficiency of the installation. All classes contain safety tests, trial operating tests, and reliability tests. This standard gives all necessary references for the contract in order to execute the test, evaluate, calculate and compare the result to the guarantee for all the classes A, B and C.