Siemens 7SR224 - Cold Load (51 C); Figure 2-4 Cold Load

7SR224 Argus Commissioning & Maintenance Guide
©2010 Siemens Protection Devices Limited Chapter 6 Page 21 of 73
2.4 Cold Load (51C)
7SR224
46
BC
46
NPS
(x2)
37
(x2)
49
50
BF
51V
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
51V
I
L2
(I
B
)
81
HBL
2
37
(x2)
49
50
BF
51V
I
L3
(I
C
)
81
HBL
2
60
CTS
60
VTS
I
4
(I
G
/I
SEF
)
74
TCS
(x3)
NOTE: The use of some
functions are mutually exclusive
67/
50
(x4)
67/
51
(x4)
67/
50
(x4)
67/
50
(x4)
67/
51
(x4)
67/
51
(x4)
64
H
27
59
27
59
(x4)
27
59
(x4)
27
59
(x4)
47
(x2)
79
59N
(x2)
Note:
Example shows
Voltage Config =
Van, Vbn, Vcn
81
(x4)
67/
50G
(x4)
67/
51G
(x4)
67/
50S
(x4)
67/
51S
(x4)
27S
59S
27S
59S
27S
59S
Batt
Test
Cap.
Test
Figure 2-4 Cold Load
Voltage Inputs: V
L1
(V
A
), V
L2
(V
B
), V
L3
(V
C
) for directional elements
Current Inputs: I
L1
(I
A
), I
L2
(I
B
), I
L3
(I
C
),
Disable: 51V, 46, 49, 50CBF, 79
Map Pickup LED: 51-n - Self Reset
The CB must be open for more than the Cold Load Pick-up Time to allow testing of this function. It may be
convenient to reduce this setting to suit the test procedure. If the CB is open throughout the tests, the Cold Load
protection settings can be tested provided that the current is not allowed to fall below the level of the Reduced
Current Level for more than the Reduced Current Time during testing. It may be convenient to set the Reduced
Current setting to Disabled for the duration of the test. The Cold Load Active output is provided and can be used
as an indication during testing.