ABB 615 series Technical Manual page 401

1MAC059074-MB A
615 series ANSI
Technical Manual
Ungrounded
100
90
Rf = 500 ohm
80
Rf = 2500 ohm
70
Rf = 5000 ohm
60
Rf = 10000 ohm
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90100
Total ground fault current (A), Rf = 0 ohm
GUID-61455001-8012-43B9-867D-AD579844CE7F V1 EN
Figure 188: Influence of fault resistance on the residual voltage magnitude in 10 kV
ungrounded and compensated networks. The leakage resistance is
assumed to be 30 times larger than the absolute value of the capacitive
reactance of the network. Parallel resistor of the compensation coil is
assumed to be disconnected.
Ungrounded
100
90
Rf = 500 ohm
80
Rf = 2500 ohm
70
Rf = 5000 ohm
60
Rf = 10000 ohm
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total ground fault current (A), Rf = 0 ohm
GUID-2565F0BD-88F7-4678-87D8-40592E9D81BC V1 EN
Figure 189: Influence of fault resistance on the residual voltage magnitude in 15 kV
ungrounded and compensated networks. The leakage resistance is
assumed to be 30 times larger than the absolute value of the capacitive
reactance of the network. Parallel resistor of the compensation coil is
assumed to be disconnected.
Resonance, K = 1
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total ground fault current (A), Rf = 0 ohm
Resonance, K = 1
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total ground fault current (A), Rf = 0 ohm
Section 4
Protection functions
Over/Under - Compensated, K = 1.2/0.8
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total ground fault current (A), Rf = 0 ohm
Over/Under‐ Compensated, K = 1.2/0.8
100
90
80
70
60
50
40
30
20
10
0
0 10 20 30 40 50 60 70 80 90 100
Total ground fault current (A), Rf = 0 ohm
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