Where
T
inv
Inverse-time delay
T
p
Time multiplier (parameter Time dial)
V Measured voltage
V
thresh
Threshold value (parameter Threshold)
k Curve constant k (parameter Charact. constant k)
α Curve constant α (parameter Charact. constant α)
c Curve constant c (parameter Charact. constant c)
Dropout
The greater dropout differential (= | pickup value – dropout value |) of the following 2 criteria
applies:
Dropout differential derived from the parameter Dropout ratio
If this parameter is not available, a dropout ratio of 95 % applies for the overvoltage and of 105 % for the
undervoltage functionality.
Minimum absolute dropout differential 150 mV sec.
Times
Operate time with time delay = 0 ms, typical
Approx. 25 ms + OOT
50
at 50 Hz
Approx. 22 ms + OOT at 60 Hz
Operate time with time delay = 0 ms, maximum Approx. 30 ms + OOT at 50 Hz
Approx. 26 ms + OOT at 60 Hz
Dropout time, typical Approx. 25 ms + OOT
Dropout time, maximum Approx. 30 ms + OOT
Frequency Operating Range
0.9 ≤ f/f
rated
≤ 1.1 According to specified tolerances
10 Hz ≤ f < 0.9 f
rated
1.1 f
rated
< f ≤ 90 Hz
Slightly expanded tolerances
f < 10 Hz
f > 90 Hz
Active
Tolerances for Stage Type Definite-Time Overvoltage Protection
Voltages
0.5 % of the setting value or 0.05 V
Time delays 1 % of the setting value or 10 ms
50
OOT (Output Operating Time): additional delay of the output medium used, see Chapter 11.1.4 Relay Outputs
Technical Data
11.19 Voltage Protection
SIPROTEC 5, Low-Impedance Busbar Protection, Manual 957
C53000-G5040-C019-C, Edition 04.2021
To Next Page
Loading...
Need help?
General
