ABB 615 Series - Page 823

R Hz R km
0
60 1 0 17765[ ] . [ / ]≈ + Ω
GUID-C33EC003-0DA2-4FFC-9496-586D7342DAF6 V1 EN (Equation 153)
X
w
r
km
n
en
0
4
2 10 3 0 25≈ ⋅ ⋅ ⋅ +






−
ω ln . [ / ]Ω
GUID-6850481D-094B-4FA0-9E73-39DCC6C49BCC V2 EN (Equation 154)
R
1
conductor AC resistance [Ω/km]
W
658
ρ
ground
n
f
GUID-B5E58636-11CC-4A89-8E3E-57023A657FDE V1 EN
the equivalent depth [m] of the ground return path
ρ
ground
ground resistivity [Ωm]
r
en
r a a a⋅ ⋅ ⋅
12
2
23
2
31
2
3
3
GUID-F7698D7C-ADCC-4555-A3C7-05DAEB3FBA70 V2 EN
the equivalent radius [m] for conductor bundle
r
radius [m] for single conductor
a
xy
distance [m] between phases x and y
Ph leakage Ris and Ph capacitive React settings
The Ph leakage Ris and Ph capacitive React settings are used for improving fault distance
estimation accuracy for ground faults. They are critical for an accurate fault location in
ungrounded networks. In other types of networks they are less critical. The Ph leakage Ris
setting represents the leakage losses of the protected feeder in terms of resistance per
phase. The Ph capacitive React setting represents the total phase-to-ground capacitive
reactance of the protected feeder per phase. Based on experience, a proper estimate for Ph
leakage Ris should be about 20…40 × Ph capacitive React.
1MAC059074-MB A Section 5
Protection related functions
615 series ANSI 817
Technical Manual