Undervoltage Protection with Any Voltage
Setting Values
Measured value Measured phase-to-ground voltage V
A
Measured phase-to-ground voltage V
B
Measured phase-to-ground voltage V
C
Measured phase-to-phase voltage V
AB
Measured phase-to-phase voltage V
BC
Measured phase-to-phase voltage V
CA
Calculated phase-to-phase voltage V
AB
Calculated phase-to-phase voltage V
BC
Calculated phase-to-phase voltage V
CA
Calculated voltage V0
Method of measurement Fundamental component
RMS value
Pickup value
38
0.300 V to 340.000 V Increments of 0.001 V
Time delay 0.00 s to 60.00 s Increments of 0.01 s
Dropout ratio 1.01 to 1.20 Increments of 0.01
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
Approx. 25 ms + OOT
39
at 50 Hz
Approx. 22 ms + OOT at 60 Hz
Dropout time Approx. 20 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 ≤ 80 Hz
Slightly expanded tolerances
f < 10 Hz
f > 80 Hz
Inactive, maintained;
Dropout of the pickup induced by blocking or by increasing the
measurand beyond the dropout threshold
Tolerances
Voltages
0.5 % of the setting value or 0.05 V
Time delays 1 % of the setting value or 10 ms
11.26
38
If you have selected the method of measurement = RMS value, do not set the threshold value under 10 V.
39
OOT (Output Operating Time) additional delay of the output medium used, see chapter 11.1.4 Relay Outputs
Technical Data
11.26 Undervoltage Protection with Any Voltage
SIPROTEC 5, Low-Impedance Busbar Protection 7SS85, Manual 607
C53000-G5040-C019-6, Edition 06.2016
To Next Page
Loading...
Need help?
General
