Underfrequency Protection
Setting Values
Pickup values f<
30.00 Hz to 70.00 Hz
Increments of 0.01 Hz
Dropout differential
20 mHz to 2 000 mHz
Increments of 10 mHz
Time delay T
0.00 s to 600.00 s
Increments of 0.01 s
Minimum voltage
3.000 V to 175.000 V
Increments of 0.001 V
Times
Pickup times f<
Angle difference method
50 Hz
60 Hz
Approx. 70 ms + OOT
64
Approx. 60 ms + OOT
Filtering method
50 Hz
60 Hz
Approx. 75 ms + OOT
Approx. 64 ms + OOT
Dropout times f<
60 ms to 80 ms
Dropout
The larger dropout differential (=
| pickup value – dropout threshold |
) of the following 2 criteria
is used:
Dropout differential derived from the parameter
Dropout ratio
If this parameter is not present, a dropout ratio of 100.03 % applies to the underfrequency protection.
Minimum absolute dropout differential
5 mHz
Operating Ranges
Voltage range
5 V to 230 V (phase-phase)
Frequency range
Angle difference method 10 Hz to 90 Hz
Filtering method
25 Hz to 80 Hz
Tolerances
Frequency f<
f
rated
- 0.20 Hz < f < f
rated
+ 0.20 Hz
± 5 mHz at V = V
rated
f
rated
- 3.0 Hz < f < f
rated
+ 3.0 Hz
± 10 mHz at V = V
rated
Time delay T(f<)
1 % of the setting value or 10 ms
Minimum voltage
1 % of the setting value or 0.5 V
Rate of Frequency Change Protection
Setting Values for the Function
Minimum voltage
3.000 V to 175.000 V
Increments of 0.001 V
Measuring window
2 periods to 5 periods
Increments of 1 period
11.20.2
11.20.3
64
OOT (Output Operating Time): Additional delay of the output medium used, for example, 5 ms with fast relays, see chapter
Technical Data
11.20 Frequency Protection
968
SIPROTEC 5, Low-Impedance Busbar Protection, Manual
C53000-G5040-C019-C, Edition 04.2021
