Technical Data
4.3 Frequency Protection 81 O/U
SIPROTEC, 7RW80, Manual
C53000-G1140-C233-1, Release date 10.2010
187
4.3
Frequency Protection 81 O/U
Setting Ranges / Increments
Times
Dropout Difference
Dropout Ratio
Tolerances
Influencing Variables
Number of frequency elements
4; each can be set to f> or f<
Pickup values f> or f<
for f
Nom
= 50 Hz
40.00 Hz to 60.00 Hz
Increments 0.01 Hz
Pickup values f> or f<
for f
Nom
= 60 Hz
50.00 Hz to 70.00 Hz
Increments 0.01 Hz
Dropout threshold
= |pickup threshold - dropout threshold|
0.02 Hz to 1.00 Hz
Increments 0.01 Hz
Time delays T
0.00 s to 100.00 s or
∞
(dis-
abled)
Increments 0.01 s
Undervoltage blocking
with three-phase connection: Positive sequence
component V
1
with single-phase connection (connection type "Vph-
n, Vsyn"): single-phase Phase-to-ground voltage
10 V to 150 V
Increments 1 V
Pickup times f>, f<
approx. 100 ms at f
Nom
= 50 Hz
approx. 80 ms at f
Nom
= 60 Hz
Dropout times f>, f<
approx. 100 ms at f
Nom
= 50 Hz
approx. 80 ms at f
Nom
= 60 Hz
Δ
f =
I
pickup value - dropout value
I
0.02 Hz to 1 Hz
Dropout Ratio for Undervoltage Blocking
approx. 1.05
Pickup frequencies 81/O or 81U
Undervoltage blocking
Time delays 81/O or 81/U
15 mHz (with V = V
nom
, f = f
Nom
±
5 Hz)
3 % of setting value or 1 V
1 % of setting value or 10 ms
Power supply direct voltage in range 0.8
≤
V
PS
/V
PSNom
≤
1.15
1 %
Temperature in range 23.00 °F (-5 °C)
≤
Θ
amb
≤
131.00 °F (55 °C)
0.5 %/10 K
Harmonics
- up to 10 % 3rd harmonic
- up to 10 % 5th harmonic
1 %
1 %