7SR11 & 7SR12 Performance Specification
ยฉ2017 Siemens Protection Devices Limited Chapter 3 Page 18 of 56
Section 2: Protection Functions
2.1 27/59 Under/over voltage
2.1.1 Reference
s
hyst
Hysteresis setting 0, 0.1โฆ 80.0%
t
d
Delay setting
0.00, 0.01โฆ20.00, 20.50โฆ 100, 101โฆ 1000, 1010โฆ
10000, 10100โฆ 14400 s
2.1.2 Operate and Reset Level
Attribute Value
V
op
Operate level
100 % Vs, ยฑ 1 % or ยฑ0.25V
Reset level
Overvoltage
= (100 % - hyst) x V
op,
ยฑ 1 % or ยฑ 0.25V
Undervoltage
= (100 % + hyst) x V
op
ยฑ 1 % or ยฑ 0.25V
Repeatability
ยฑ 1 %
Variation
-10 ยฐC to +55 ยฐC
โค 5 %
f
nom
ยฑ 5 %
โค 5 %
2.1.3 Operate and Reset Time
Attribute Value
t
basicE
Element basic
operate time
Overvoltage
0 to 1.1 x Vs: 73 ms, ยฑ 10ms
0 to 2.0 xVs: 63 ms, ยฑ 10ms
Undervoltage
1.1 to 0.5 xVs: 58 ms, ยฑ 10ms
t
op
Operate time following delay
t
basic
+ t
d
, ยฑ 1 % or ยฑ 10ms
Repeatability
ยฑ 1 % or ยฑ 10ms
Disengaging time < 80 ms