A multi-protection system using operation signals of protection components in separate relays is provided to generate a trip signal for stopping a generator only when trip signals are received from two or more protection signals. A multi-protection system using operation signals of protection components in separate relays is formed by using three protection relays. The protection relays generate trip signals by detecting a failure of a generating system. Each of the protection relays includes input units(11,21,31), 2 out of 3 logic units(13,23,33), 1 out of 2 logic units(14,24,34), a failure detecting unit, a cut-off unit, and control units(12,22,32). The input units receives the operation signals of the different protection relays. The 2 out of 3 logic units and the 1 out of 2 logic units compare the operation signals of the protection components inputted through the input units. The failure detecting unit detects a non-contact state when the non-contact state of the protection relay occurs. The cut-off unit stops the generator through a 2 out of 3 logic or a 1 out of 2 logic. The control units allow the selection of the 2 out of 3 logic units and the 1 out of 2 logic units.
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