Siemens 7SR18 Solkor - Phase Overcurrent (50, 51)

7SR18 Commissioning & Maintenance Guide
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of
3.1 PHASE OVERCURRENT (50, 51)
46
BC
46
NPS
(x2)
37 (x2) 49
50
BF
VL1
VL2
VL3
IL1
37 (x2) 49
50
BF
IL2
37 (x2) 49
50
BF
IL3
60
CTS
I4
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)
27
59
(x4)
27
59
(x4)
27
59
(x4)
59N (x2)
50 BF
47
51V
51V
51V
64H
51c
81HBL2
81HBL237
81
(x4)
60
VTS
87L
Diff (x2)
87L
Diff (x2)
87L
Diff (x2)
79
Ordering Options
74TCS
(x3)
74CCS
(x3)
86
81HBL2
81HBL2
51c
51c
Figure 3.1-1 Phase Overcurrent
Current Inputs: I
L1
(I
A
), I
L2
(I
B
), I
L3
(I
C
),
Disable: 51C, 46, 49, 50CBF
Map Pickup LED: 51-n/50-n - Self Reset
Other protection functions may overlap with these functions during testing, it may be useful to disable some
functions to avoid ambiguity. It should be particularly noted that if the function is enabled, the 51C Cold Load
settings may modify the normal 50-n and 51-n settings if the CB is open during testing.
Particular care should be taken when testing overcurrent functions that the thermal rating of the current inputs is
not exceeded.