10.2.1
Identification
Function description
IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Overfrequency protection
SAPTOF
f >
SYMBOL-O V1 EN
81
10.2.2
Functionality
Overfrequency protection function SAPTOF is applicable in all situations, where
reliable detection of high fundamental power system frequency is needed.
Overfrequency occurs because of sudden load drops or shunt faults in the power
network. Close to the generating plant, generator governor problems can also cause
over frequency.
SAPTOF measures frequency with high accuracy, and is used mainly for generation
shedding and remedial action schemes. It is also used as a frequency stage initiating
load restoring. A definite time delay is provided for operate.
SAPTOF is provided with an undervoltage blocking.
10.2.3
Function block
SAPTOF
U3P*
BLOCK
TRIP
START
BLKDMAGN
IEC09000280_1_en.vsd
IEC09000280 V1 EN
Figure 105:
SAPTOF function block
10.2.4
Signals
Table 159:
SAPTOF Input signals
Name
Type
Default
Description
U3P
GROUP
SIGNAL
-
Three phase group signal for voltage inputs
BLOCK
BOOLEAN
0
Block of function
1MRK 504 135-UEN A
Section 10
Frequency protection
235
Technical manual
Summary of Contents for ret650
Page 1: ...Relion 650 series Transformer protection RET650 Technical manual ...
Page 2: ......
Page 40: ...34 ...
Page 62: ...56 ...
Page 84: ...78 ...
Page 208: ...202 ...
Page 376: ...370 ...
Page 414: ...408 ...
Page 530: ...524 ...
Page 562: ...556 ...
Page 620: ...614 ...
Page 668: ...662 ...
Page 669: ...663 ...