Siemens Argus 7SR21 - Under;Over Frequency; Operate and Reset Level; Operate and Reset Time; Reference

7SR21 & 7SR22 Performance Specification
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2.24 81 Under/Over Frequency
2.24.1 Reference
Parameter Value
Fs Setting 40, 40.01… 69.99 Hz
Hyst Hysteresis setting 0, 0.1… 80 %
td Delay setting
0.00, 0.01… 20.0, 20.1… 100.0, 101.…1000, 1010 … 10000 ,
10100 … 14400 s
2.24.2 Operate and Reset Level
Attribute Value
F
op
Operate level
100 % F
s
, ± 10 mHz
Reset level
overfrequency
(100 % - hyst) xF
op,
± 10 mHz
underfrequency
(100 % + hyst) xF
op,
± 10 mHz
Repeatability
± 1 %
Variation - 10 °C to + 55 °C
£ 5 %
2.24.3 Operate and Reset Time
Attribute Value
t
basic
Element basic
operate time
(for ROCOF
between 0.1
and 5.0 Hz/sec)
overfrequency
Typically < 110 ms
Maximum < 150 ms
underfrequency
Typically < 110 ms
Maximum < 150 ms
t
op
Operate time following delay
t
basic
+ t
d
, ± 1 % or ± 10 ms
Repeatability
± 1 % or ± 10 ms
Disengaging time
< 100 ms