8.3.6.3 Design
ANSI08000009_en_1.vsd
RESTORE
PICKUP
PICKUP
TRIP
Pickup
&
Trip
Output
Logic
BLOCK
Frequency
100 ms
Comparator
If
[PUFreqGrad<0
AND
df/dt < PUFreqGrad]
OR
[PUFreqGrad>0
AND
df/dt > PUFreqGrad]
Then
PICKUP
Comparator
f > RestoreFreq
OR
Definite Time Delay
tTrip
tRestore
BLKDMAGN
Rate-of-Change
of Frequency
BLOCK
freqNotValid
ANSI08000009 V1 EN
Figure 85: Schematic design of Rate-of-change frequency protection SAPFRC (81)
8.3.7 Technical data
Table 148: SAPFRC (81) technical data
Function
Range or value Accuracy
Operate value, pickup function (-10.00-10.00) Hz/s ± 10.0 mHz/s
Operate value, restore enable
frequency
(45.00 - 65.00) Hz ± 2.0 mHz
Timers (0.000 - 60.000) s <130 ms
Operate time, pickup function At 50 Hz: 100 ms typically
At 60 Hz: 80 ms typically
-
Section 8 1MRK 511 287-UUS A
Frequency protection
202
Technical manual