Toshiba GRD140 Instruction Manual

⎯ 4 ⎯6 F 2 S 0 7 5 8ContentsSafety Precautions 11. Introduction 82. Application Notes 102.1 Overcurrent and Undercurrent Protection 102.1.1 Non-directional Overcurrent Protection 102.1.2 Directional Overcurrent Protection 172.1.3 Scheme Logic 212.1.4 Phase Undercurrent Protection 442.1.5 Thermal Overload Protection 462.1.6 Broken Conductor Protection 492.1.7 Breaker Failure Protection 522.1.8 Cold Load Protection 552.1.9 CT Requirements 582.2 Overvoltage and Undervoltage Protection 602.2.1 Phase Overvoltage Protection 602.2.2 Phase Undervoltage Protection 632.2.3 Zero Phase Sequence Overvoltage Protection 662.2.4 Negative Phase Sequence Overvoltage Protection 692.3 Frequency Protection 712.4 Trip and Alarm Signal Output 732.5 Autoreclose 752.5.1 Scheme Logic 752.5.2 Sequence Coordination 762.5.3 Setting 773. Technical Description 803.1 Hardware Description 803.1.1 Outline of Hardware Modules 803.2 Input and Output Signals 843.2.1 AC Input Signals 843.2.2 Binary Input, Output Signals 843.2.3 Binary Output Signals 883.3 Automatic Supervision 893.3.1 Basic Concept of Supervision 893.3.2 Relay Monitoring 893.3.3 CT Failure Supervision 903.3.4 VT Failure Supervision 913.3.5 Trip Circuit Supervision 923.3.6 Circuit Breaker Monitoring 933.3.7 Failure Alarms 943.3.8 Trip Blocking 953.3.9 Setting 96