IS/IEC 60255 : Part 181 : 2019 Measuring Relays and Protection Equipment Part 181 Functional Requirements for Frequency Protection

ICS 29.120.70

ETD 35

Reaffirmed 2024

NATIONAL FOREWORD

This Indian Standard (Part 181) which is identical with IEC 60255-181 : 2019 ‘Measuring relays and protection equipment — Part 181: Functional requirements for frequency protection’ issued by the International Electrotechnical Commission (IEC) was adopted by the Bureau of Indian Standards on recommendation of the Power System Relays Sectional Committee and approval of Electrotechnical Division Council.

This Indian Standard is published in several parts. The other parts in this series are:

Part 1 Common requirements

Part 5 Insulation coordination for measuring relays and protection equipment — Requirements and tests

Part 8 Thermal electrical relays

Part 11 Voltage dips short interruptions variations and ripple on auxiliary power supply port

Part 12 Directional relays and power relays with two input energizing quantities

Part 13 Biased percentage differential relays

Part 24 Common format for transient data exchange comtrade for power system

Part 25 Electromagnetic emission tests for measuring relays and protection equipment

Part 26 Electromagnetic compatibility requirements

Part 27 Product safety requirements

Part 121 Functional requirements for distance protection

Part 127 Functional requirements for over under voltage protection

Part 151 Functional requirements for over under current protection

The text of the IEC Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain terminologies and conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’.

b) Comma (,) has been used as a decimal marker, while in Indian Standards, the current practice is to use a point (.) as the decimal marker.