European Standards for Relay Protection are an essential aspect of electrical power network transmission and distribution. These standards provide guidelines and regulations for the design, implementation, and operation of relay protection systems in Europe. This handbook covers the code of practice in protection circuitry including standard lead and device numbers, mode of connections at terminal strips, colour codes in multicore cables, dos and donts in execution. While this is bad, It's not a. This document is in accordance with the provisions of GB/T 1. They ensure the reliability and safety. In addition, the Commission approves one new definition and six revised violation severity levels, and NERC's implementation plan.