The fault identification system includes a first logic circuit which is responsive to conventional protective elements which recognize the presence of low resistance single line-to-ground faults for the A, B and C phases on a power transmission line. The first logic circuit includes a portion thereof...http://www.google.de/patents/US6525543?utm_source=gb-gplus-sharePatent US6525543 - Fault type selection system for identifying faults in an electric power system
