Siemens 7SR18 Solkor - 60 CTS & 60 CTS-I Current Transformer Supervision; Reference; Current & Voltage Threshold; Operate and Reset Time

7SR18 Performance Specification
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3.3 60CTS & 60CTS-I Current Transformer Supervision
3.3.1 Reference
Parameter Value
I
thresh
Current Threshold 0.05, 0.1… 2 xIn
I
Applied Current
(for operate time)
Healthy CT
Phases
5 x I
thresh
Failed CT phase
0
t
d
Delay setting
0.3, 20.00, 20.50… 100, 101…
1000, 1010… 10000, 10100…
14400 s
Directional Relays have additional VT settings
V
thresh
Voltage Threshold 7, 8… 110V
3.3.2 Current & Voltage Threshold
Attribute Value
I
op
CT failed current level
100 % I
thresh
, ± 5 % or ± 1 % In
Reset level
90 % I
op,
± 5 % or ± 1 % In
V
op
CT failed voltage level 100 % V
thresh
, ± 2% or ± 0.5V
Reset level 110 % V
op
, ± 2 % or ± 0.5V
Repeatability
± 1 %
Variation
-10 °C to +55 °C
≤ 5 %
f
nom
± 5 %
harmonics to f
cutoff
≤ 5 %
3.3.3 Operate and Reset Time
Attribute Value
t
basic
Basic operate time 50 ms
±
20 ms
Operate time t
d
+ t
basic
,
±
1 % or
±
20 ms
Repeatability
± 1 % or ± 20 ms