Settings - ABB RELION 620 Series Technical Manual

1MAC504801-IB E
10.2.6
Table 570: FLO Group settings
Parameter Values (Range)
Phase level 0.05...5.00
620 series ANSI
Technical Manual
The fault location algorithm is most applicable for radial feeder. The algorithm is based on
the system model shown in
homogeneous radial distribution line. Therefore, the unit is not intended to be used on a
distribution line with many different types of conductors because the algorithm is not as
accurate. Fault location algorithm may not be accurate for the switch-onto-fault condition.
Zs
Irly
Vs
GUID-E6497F03-F9A7-4C93-9620-61842BB44774 V1 EN
Figure 399: System model considered for fault location
where:
V Source voltage
s
V Voltage at the protection relay location
rly
I Current in the transmission line at the protection relay location
rly
Z Source impedance
s
ZL Transmission line impedance in ohm/unit length
ZD Load impedance
RF Fault resistance
M Distance to point of fault from relay location

Settings

Unit Step
xIn 0.01
Figure 399. The algorithm was designed to be used on a
Total Length of the line
M
A F
ZL*M
Vrly
RF
Default Description
0.10 Phase Level
Section 10
Recording functions
B
ZL*(1-M)
ZD
789