1 CHAPTER OVERVIEW
The P24DM, P24NM provides a wide range of current protection functions. This chapter describes the operation of
these f
unctions including the principles, logic diagrams and applications.
This chapter contains the following sections:
Chapter Overview 73
Thermal Overload Protection 74
Overcurrent Protection Principles 84
Phase Overcurrent Protection 94
Current Setting Threshold Selection 101
Negative Sequence Overcurrent Protection 102
Earth Fault Protection 109
Sensitive Earth Fault Protection 130
Cold Load Pickup 138
Selective Logic 141
Timer Setting Selection 142
Blocked Overcurrent Protection 143
Second Harmonic Blocking 146
Stall protection 148
Number of Starts 158
Anti-Backspin Protection 162
P24xM Chapter 6 - Current Protection Functions
P24xM-TM-EN-2.1 73