T
Inv
Inverse-time delay
T
add
Additional time delay (Parameter
Additional time delay
)
[fo_UVP3ph_1_3pol_inverse, 2, en_US]
Where
T
Inv
Inverse-time delay
T
p
Time multiplier (Parameter
Time dial
)
V
Measured undervoltage
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
Pickup time
Approx. 25 ms + OOT
65
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 ≤ 90 Hz
Slightly expanded tolerances
f < 10 Hz
f > 90 Hz
Inactive
Tolerances for Stage Type Definite Time-Undervoltage Protection
Voltages
0.5 % of the setting value or 0.05 V
Currents
1 % of the setting value or 5 mA (I
rated
= 1 A) or 25 mA (I
rated
= 5 A, f
rated
±
10 %), valid for protection-class current transformers
1 % of the setting value or 0.1 mA (I
rated
= 1.6 A) or 0.5 mA (I
rated
= 8 A,
f
rated
± 10 %), valid for instrument transformers
Time delays
1 % of the setting value or 10 ms
65
OOT (Output Operating Time) additional delay of the output medium used, see chapter
Technical Data
12.10 Voltage Protection
840
SIPROTEC 5, Merging Unit 6MU85, Manual
C53000-G5040-C074-1, Edition 01.2020