Restricted Earth Fault (64H) - Siemens 7SR224 Technical Manual

2.8

Restricted Earth fault (64H)

I
(I /I
G
V
(V
V
(V
V
(V
(V
Figure 2-9 Restricted Earth Fault
Voltage Inputs:
Current Inputs:
Disable: 51SEF, 50SEF, 79
Map Pickup LED:
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
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.
Apply 2x setting current if possible and record operating time
©2010 Siemens Protection Devices Limited
37 50
49
(x2) BF
I
L1
(I )
A
37 50
49
(x2) BF
I
L2
(I )
B
37 50
49
(x2) BF
I
L3
(I )
C
46
46 60
NPS
BC CTS
(x2)
67/
64
50G
H
4 (x4)
)
SEF
NOTE: The use of some
functions are mutually exclusive
27
27S
L1
59
) 59S
A
(x4)
27
27S
L2
59
) 59S
B
(x4)
27
27S
L3
59
) 59S
C
(x4)
V 27
4
) 59
X
n/a
I (I )
4 REF
64H - Self Reset
7SR224 Argus Commissioning & Maintenance Guide
7SR224
67/ 67/ 81
51V 50 51 HBL
(x4) (x4) 2
67/ 67/ 81
51V 50 51 HBL
(x4) (x4) 2
67/ 67/ 81
51V 50 51 HBL
(x4) (x4) 2
60
VTS
67/ 67/ 67/
51G 50S 51S
(x4) (x4) (x4)
Note:
Example shows
Voltage Config =
47
81 Van, Vbn, Vcn
(x2) (x4)
74
59N Batt
TCS
Test
(x2)
(x3)
Cap.
79
Test
Measured
Chapter 6 Page 33 of 73