P12x/EN T/Eb6 - Schneider - error

Application GuideP12x/EN AP/Eb6MiCOM P120/P121/P122/P123 Page 1/78CONTENTS1. INTRODUCTION 51.1 Protection of Underground and Overhead Lines 52. EARTH AND PHASE CURRENT OVERCURRENT FUNCTIONS 62.1 Instantaneous function (50/50N) (P122 and P123 relays) 72.2 Derived earth overcurrent threshold (Ie>>>>, P122 and P123 only) 72.3 Ie>…Ie>>…Ie>>> Interlock 82.4 DMT thresholds 82.5 IDMT thresholds 82.5.1 Inverse time curves 82.5.2 RXIDG curves 92.6 Reset timer 102.6.1 Reset timer (P122 & P123 only) 102.7 Time graded protection 113. TRANSFORMER INRUSH CURRENT (P122 & P123 ONLY) 123.1 Overview 123.2 Operation 123.2.1 Principle 154. BUSBAR PROTECTION ON RADIAL SYSTEMS 165. BLOCKING LOGIC FUNCTION (BLOCKED OVERCURRENTPROTECTION) 176. RESTRICTED EARTH FAULT 186.1 Introduction 186.2 High impedance principle 196.3 Setting guide 206.3.1 CT requirements for High Impedance Restricted Earth Fault Protection 216.4 Use of METROSIL non linear resistors 216.4.1 Metrosil units for relays with 1A CT 226.4.2 Metrosil units for relays with 5A CT 237. RECTIFIER PROTECTION 248. BACK-UP DIAGRAM USING « TRANSFERRED SELECTIVETRIPPING » 269. REMOTE PROTECTION STAND-BY DIAGRAM 2810. 1 ½ BREAKER SCHEME 29