IS 12746 : Part 4 : 1993/IEC PUB 870-4 : 1990 Telecontrol equipment and systems: Part 4 Performance requirements

National Foreword

This Indian Standard, which is identical with IEC Pub 870-4(1990) `Telecontrol equipment and systems - Part 4 : Performancerequirements' issued by the International ElectrotechnicalCommission (IEC), was adopted by the Bureau of Indian Standards onthe recommendation of the Power Line Carrier Systems and AssociatedTelecontrol Equipment Sectional Committee (LTD 25) and approval ofthe Electronics and Telecommunication Division Council.

The text of the IEC Pub has been approved as suitable forpublication as Indian Standard without deviations. Certainconventions are, however, not identical to those used in IndianStandards. Attention is particularly drawn to This:

a) Wherever the words `International Standard' appear referringto this standard, they should be read as `Indian Standard'.

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