1MRS758734
4.
4.1.
4.2.
4.3.
COM600 series 5.1
Substation Analytics Technical Manual
Fault locator SCEFRFLO
Identification
Function Description
IEC 61850 identifica-
tion
Fault locator function
SCEFRFLO
Functionality
The fault locator function FaultLocator_sc_A provides impedance-based fault location.
It is designed for radially operated distribution systems. It is applicable for locating short
circuits in all kinds of distribution networks. Earth faults can be located in effectively
earthed and in low-resistance/low-reactance earthed networks. Under certain limitations,
FaultLocator_sc_A can also be applied for an earth fault location in unearthed distribution
networks.
The fault distance calculation is based on locally measured fundamental frequency current
and voltage phasors. The full operation of FaultLocator_sc_A can requires that all three
currents and phase-to-earth voltages are measured.
The fault distance calculation is done in two steps. The fault type is determined first
using the build-in Phase Selection Logic PSL. After this, the fault distance is calculated.
The fault locator report function SCEFRFRP function provide a report recoding mech-
anism to create report to use in the COM600 WebHMI.
Operation Principle
The function can be enabled or disabled with the Operation setting. The corresponding
parameter values are "On" and "Off".
The actual fault distance calculation consists of two steps. The fault type is determined
first by using the built-in phase selection logic PSL. After this, the fault distance is cal-
culated. As a fundamental operation criterion, the maximum of the phase current mag-
nitudes must exceed a threshold value of 1 percent of the nominal phase current value
of the CT primary current. When this condition is not met, all the outputs of the function
are blocked.
IEC 60617 identifica-
ANSI/IEEE identifica-
tion
tion
FLOC
21FL
13