7SR11 & 7SR12 Commissioning and Maintenance Guide
ยฉ2017 Siemens Protection Devices Limited Chapter 6 Page 62 of 72
3.2 Voltage Transformer Supervision (60VTS)
7SR12
46
BC
46
NPS
(x2)
37
(x2)
49
50
BF
51V
V
L1
(V
A
)
V
L2
(V
B
)
V
L3
(V
C
)
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
I
4
(I
G
)
74
T/
CCS
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/
50
SEF
67/
51
SEF
27
59
(x4)
27
59
(x4)
27
59
(x4)
47
(x2)
81
(x6)
79
Optional
59N
(x2)
Note:
Example shows
Voltage Config =
Van, Vbn, Vcn
60
CTS
60
VTS
50
BF
51c
51c
51c
64H
Figure 2-23 Voltage Transformer Supervision
Voltage Inputs: V
L1
(V
A
), V
L2
(V
B
), V
L3
(V
C
)
Current Inputs: I
L1
(I
A
), I
L2
(I
B
), I
L3
(I
C
),
Disable: 27, 47, 59N
Map Pickup LED: 60VTS - Self Reset
3.2.1 1 or 2 Phase VT fail
Apply 3P balanced nominal current and voltage. Reduce 1 phase voltage until VTS operates, record voltage
reduction level.
Measured Voltage Reduction
Increase the voltage until VTS resets. Increase current on 1 phase by 110% of 3x the 60VTS I setting. Reduce
voltage as above and check for no operation. Return voltage to nominal. Increase current on 1 phase by 90% of
3x the 60VTS I setting. Reduce voltage as above and check for VTS operation