Advertisement
Power Automation and Protection Division
for single line to ground faults,
for line to line faults, and
for three-phase faults.
The algorithm has limitations, especially when REL 352 is being applied to lines with series ca-
pacitors. The above equations represent the apparent impedance to the relay and do not ac-
count for the presence of the series negative reactance. The user should account for this in the
final estimate.
This function is included in REL 352 when the optional distance back-up system is included.
REL 352 Version 1.00
Z
=
(V
- V
XY
XG
YG
Z
=
V
/ I
ABC
A
A
(X, Y
=
Any A, B, C phase)
) / (I
- I
)
X
Y
I.L. 40-201.9
3
3-9
Advertisement
