1 CHAPTER OVERVIEW
This chapter consists of the following sections:
1
Chapter Overview
2 Protection functions
2.1 Overcurrent Protection Principles
2.1.1 IDMT Characteristics
2.1.2 Principle of Protection Function Implementation
2.1.3 Timer Hold Facility/Reset Characteristics
2.2 Phase Overcurrent Protection
2.2.1 Phase Overcurrent Protection Implementation
2.3 Negative Sequence Overcurrent Protection
2.3.1 Negative Sequence Overcurrent Protection Implementation
2.3.2 Negative Sequence Overcurrent Protection Logic
2.4 Earth Fault Protection
2.4.1 Earth Fault Protection Elements
2.4.2 Earth Fault Protection Logic
2.5 Thermal Overload Function
2.5.1 Thermal Overload Protection Implementation
2.6 Broken Conductor
2.6.1 Broken Conductor Protection Implementation
2.6.2 Broken Conductor Protection Logic
2.7 Undercurrent /Loss of Power Protection Function
2.8 Circuit Breaker Fail Protection
2.8.1 Circuit Breaker Fail Implementation
2.8.2 Circuit Breaker Fail Logic
2.9 Cold Load Pickup Function
2.9.1 Cold Load Pickup Logic
2.9.2 Cold Load Pickup for SWITCH ONTO FAULT Condition
2.10 Inrush Current Blocking Function (2ND Harm Blocking)
2.10.1 Second Harmonic Blocking Implementation