Voltage
START
START
TRIP
Start
&
Trip
Output
Logic
Time integrator
Definite Time Delay
TimeDlyOperate
TimeDlyReset
Comparator
U < IntBlockLevel
BLOCK
en05000735.vsd
Frequency Comparator
f > StartFrequency
TRIP
BLKDMAGN
BLOCK
OR
BLKTRIP
IEC05000735 V1 EN
Figure 83: Schematic design of overfrequency protection SAPTOF
8.2.8 Technical data
Table 144: SAPTOF technical data
Function
Range or value Accuracy
Operate value, start function (35.00-75.00) Hz ± 2.0 mHz at
symmetrical three-
phase voltage
Reset ratio
>0.999 -
Operate time, start function At 50 Hz: 200 ms typically at f
set
-0.5 Hz to f
set
+0.5 Hz
At 60 Hz: 170 ms typically at f
set
-0.5 Hz to f
set
+0.5 Hz
-
Reset time, start function At 50 and 60 Hz: 55 ms typically at f
set
+0.5 Hz
to f
set
-0.5 Hz
-
Timer (0.000-60.000)s <250 ms
8.3 Rate-of-change frequency protection SAPFRC
Section 8 1MRK 511 287-UEN A
Frequency protection
186
Technical manual