Sel 411L - Page 109

Date Code 20151029 Protection Manual SEL-411L Relay
Section 3
P.Protection Manual
Protection Functions
This section provides a detailed explanation for each of the many relay
protection functions. Each subsection provides an explanation of the function,
along with a list of the corresponding settings and Relay Word bits. Logic
diagrams and other figures are included.
Functions discussed in this section are listed below.
➤ 87L Theory of Operation on page P.3.2
➤ 87L Differential Elements on page P.3.28
➤ Current and Voltage Source Selection on page P.3.106
➤ Polarizing Quantity for Distance Element Calculations on
page P.3.119
➤ Frequency Estimation on page P.3.119
➤ Time-Error Calculation on page P.3.122
➤ Fault Location on page P.3.123
➤ Open-Phase Detection Logic on page P.3.134
➤ Pole Open Logic on page P.3.134
➤ Loss-of-Potential Logic on page P.3.137
➤ Fault Type Identification Selection Logic on page P.3.141
➤ Ground Directional Element on page P.3.142
➤ Phase- and Negative-Sequence Directional Elements on
page P.3.152
➤ Directionality on page P.3.154
➤ CVT Transient Detection on page P.3.154
➤ Series-Compensation Line Logic on page P.3.155
➤ Load-Encroachment Logic on page P.3.156
➤ Out-of-Step Logic (Conventional) on page P.3.157
➤ Out-of-Step Logic (Zero Settings) on page P.3.163
➤ Mho Ground-Distance Elements on page P.3.178
➤ Quadrilateral Ground-Distance Elements on page P.3.182
➤ Mho Phase Distance Elements on page P.3.186
➤ Quadrilateral Phase Distance Elements on page P.3.191
➤ Zone Time Delay on page P.3.197
➤ Instantaneous Line Overcurrent Elements on page P.3.200
➤ Over/Undervoltage Elements on page P.3.213
➤ Selectable Time-Overcurrent Elements (51) on page P.3.205