Protection Functions
150 PRS-7367
location greatly decreases the downtime of the protected lines and increases the total availability
of a power system. 21FL provides the distance to the fault together with the information about the
measuring loop that has been used in the calculation. Also, an estimate for the fault resistance at
the fault point is calculated.
3.28.4 21FL Settings
Table 3.28-3 21FL Settings
The positive sequence impendence
amplitude
The positive sequence impendence
angle
The zero sequence impendence
coefficient
3.29 Reverse power protection 32R
3.29.1 32R Overview
The feeder relay provides a two-stage power protection with independent definite time delay
characteristics, and each stage has the same protection logics.
This function contains a blocking functionality. It is possible to block the function outputs, timer
or the function itself, if desired.
3.29.1.1 Function Block
The function block of the protection is as below.
Figure 3.29-1 Function block
3.29.1.2 Signals
Table 3.29-1 Input Signals