7SR18 Performance Specification
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Section 2: Protection Functions
2.1 37 Undercurrent
2.1.1 Reference
Parameter Value
Is Setting 0.05, 0.10…5.0 xIn
t
d
Delay setting
0.00, 0.01…20.00, 20.10… 100, 101… 1000, 1010…
10000, 10100… 14400 s
2.1.2 Operate and Reset Level
Attribute Value
I
op
Operate level
100 % Is, ± 5 % or ± 1 % In
Reset level
≤ 105 % I
op
Repeatability
± 1 %
Variation
-10 °C to +55 °C
≤ 5 %
f
nom
± 5 %
≤ 5 %
2.1.3 Operate and Reset Time
Attribute Value
t
basic
Element basic operate time
1.1 to 0.5 xIs: 35 ms, ± 10 ms
t
op
Operate time following delay
t
basic
+ t
d
, ± 1 % or ± 10 ms
Repeatability
± 1 % or ± 10 ms
Overshoot time < 40 ms
Disengaging time < 60 ms