There are two types of stator protection systems a) 95% scheme which covers the 95% of the winding excluding 5% from the neutral, which is based on the third harmonic measurement. b) 100% stator protection system covers the full range including the 5% closer to the neutral, and this is based on sub-harmonic injection method. Besides, in this 100% scheme, the faults can be detected even in generator shutdown condition, which is not possible in the 95% scheme.