PURPOSE: To prevent the setting element selection and setting operation of setters from being dropped out, by displaying a plurality of setting elements and setting values for the elements, in a first and a second display means.

CONSTITUTION: Each current on the primary side and secondary side of a protected transformer T1 is respectively transformed by main current transformers CT1, CT2, and the input to an input converter 10 is provided. The input of the output of the input converter 10, to a relay 11 is provided. The relay 11 consists of a setting section 2 for setting reference current on the primary side and secondary side of the protected transformer T1 and the ratio of the current transformation of the main current transformers CT1, CT2, and a relay discriminating section 12. The setting section 2 has a first display means for displaying the main current transformers CT1, CT2 of setting elements, and a second display means for displaying setting values for the setting elements.