7SR210 & 7SR220 Commissioning & Maintenance Guide
Page 22 of 82 © 2013 Siemens Protection Devices Limited
2.4 Cold Load (51c)
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 2.4-1 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, 50BF, 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.
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