scope:

This Standard specifies requirements for overcurrent relays (hereafter referred to asrelays) which are installed at power receiving points of 6.6 kV consumers for the purpose of protecting the electrical circuits against short circuits and overloads. Requirements for digital relays are provided in the main body, and those for analogue relays, in Annex JD.

NOTE The International Standard corresponding to this Standard and the symbol of degree of correspondence are as follows.

IEC 60255-151 :2009 Measuring relays and protection equipment-Part 151: Functional requirements for over/under current protection (MOD)

In addition, symbols which denote the degree of correspondence in the contents between the relevant International Standard and JIS are IDT (identical), MOD (modified), and NEQ (not equivalent) according to ISO/ IEC Guide 21-1.