SHORT-TO-GROUND DETECTOR FOR WINDINGS

The invention relates to a method for detection of a ground fault ( 18 ), which occurs in the vicinity of a neutral point ( 22 ), in a polyphase electrical device which is operated at a fundamental frequency, in particular an electrical machine ( 10 ) or a transformer which has a number of windings ( 11, 12, 13 ), which are associated with the individual phases, one end of each of which windings ( 11, 12, 13 ) is connected to the neutral point ( 22 ) and the other end of each of which windings ( 11, 12, 13 ) is connected directly to a power supply network via a power supply system connection ( 14, 15, 16 ). Simple and reliable detection is achieved in that the change in the physical variables which is associated with a ground fault ( 18 ) is measured in the immediate vicinity of the ground fault ( 18 ), and is evaluated.