Manual MRG3
SEG Electronics GmbH
DOK-TD-MRG3, Rev. D
81
7.8.5 Earth fault supervision with directional feature
Setting range
Step
(range)
Tolerance
U0>
3pha: 1
– 86%
e-n:
1 - 86 %
1:1:
1 - 150 %
1
(1...150)
2% of the set value or 1 %
from U
N
I
E
>
1...45 % (EXIT)
0.1
(1...5)
0.2
(5...10)
0.5
(10...20)
1
(20...45)
3% of the set value
or
0.3% I
N
tI
E
>V*
tI
E
>R**
0,1 - 300 s (EXIT)
(definite time)
0.1
(0.1...5.0)
0.2
(5.0...10.0)
0.5
(10...20)
1.0
(20...50)
2.0
(50...100)
5.0
(100...200)
10.0
(200...300)
3% bzw.
80 ms
I
E
>>
1...45 % (EXIT)
0.1
(1...5)
0.2
(5...10)
0.5
(10...20)
1
(20...45)
3% of the set value
or
0.3% I
N
tI
E
>>V*
tI
E
>>R**
0.1... 300 s (EXIT)
0.1
(0.1...5.0)
0.2
(5.0...10.0)
0.5
(10...20)
1.0
(20...50)
2.0
(50...100)
5.0
(100...200)
10.0
(200...300))
3% or
80 ms
Table 7.5: Earth fault supervision with directional feature
* Tripping time in forward direction (tripping range)
** Tripping time in backward direction (blocking range), see chapter 4.7.3
7.8.6 Determination of the earth fault direction (MRG3-IER)
Measurement of the energy
component of current in
compensated grids:
I
E
x cos
Measurement of the reactive
current component in
isolated grids:
I
E
x sin
Accuracy of angular
measurement:
3° at I
E
x cos
bzw. I
E
x sin
>5% I
E
Sensitive of the
residual voltage:
>2% U
0N
bei I = 0.1 x I
EN