an inductive rotating power transfer circuit , preferably for transferring electrical power from the stationary part to the rotating part of a ct scanner comprises an inductive power transformer having a stationary primary side and a rotating secondary side . the secondary side is connected via a rectifier to a filtering capacitor , delivering electrical power to a load . one of the output pins of the filtering capacitor is connected to a secondary ground at the rotating part which is further connected to a stationary protective ground via a galvanic slip ring . in the case of a short circuit between a secondary transformer winding and the secondary ground , the secondary winding is partially short - circuited by one of the rectifier diodes . this causes an asymmetric current load at the primary side and a current flowing through the slip ring . both currents may be used to detect a failure of the secondary winding .