7SR210 & 7SR220 Commissioning & Maintenance Guide
© 2013 Siemens Protection Devices Limited Page 39 of 82
2.6 Restricted Earth fault. (64H)
7SR22
46
BC
46
NPS
(x2)
37
(x2)
49
50
BF
V
L1
(V
A
)
V
L2
(V
B
)
V
L3
(V
C
)
V
4
(V
X
)
I
L1
(I
A
)
81
HBL
2
37
(x2)
49
50
BF
I
L2
(I
B
)
81
HBL
2
37
(x2)
49
50
BF
I
L3
(I
C
)
81
HBL
2
60
CTS
I
4
(I
G
)
I
5
(I
SEF
)
74
TCS
NOTE: The use of some
functions are mutually exclusive
67/
50
(x4)
67/
51
(x4)
67/
50N
(x4)
67/
50
(x4)
67/
50
(x4)
67/
51
(x4)
67/
51
(x4)
67/
51N
(x4)
67/
50G
(x4)
67/
51G
(x4)
67/
50S
(x4)
67/
51S
(x4)
64
H
27
59
27
59
(x4)
27
59
(x4)
27
59
(x4)
47
(x2)
81
(x6)
79
Optional
59N
(x2)
81
HBL
2N
60
VTS
51V
51V
51V
37G
(x2)
37S
(x2)
51c
60
CTS-
I
60
CTS-
I
60
CTS-
I
37
50
BF
37
50
BF
25
50
AFD
50
AFD
50
AFD
51c
51c
51c
Figure 2.6-1 Restricted Earth Fault
Voltage Inputs: n/a
Current Inputs: I
5
(I
REF
)
Disable: 51SEF, 50SEF, 79
Map Pickup LED:. 64H - Self Reset
The setting resistance should be measured and the value compared to that specified in the settings data. Both
values should be recorded.
Settings Data Resistor Value Measured
The high value of setting resistance R will often interfere with secondary current injection when using a digital test
set. It is normal practice in these cases to short out the resistor to allow testing; the shorting link should be
removed after testing.
Since the DTL setting is generally small the pick-up setting can be tested by gradually increasing current until
element operates. The relay should be disconnected from the current transformers for this test.
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