ABB RED650 - Section 10 Frequency Protection; Underfrequency Protection SAPTUF; Identification; Functionality

Section 10 Frequency protection
10.1 Underfrequency protection SAPTUF
IP15746-1 v3
10.1.1 Identification
M14865-1 v5
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Underfrequency protection SAPTUF
f <
SYMBOL-P V1 EN-US
81
10.1.2 Functionality
M13349-3 v13
Underfrequency occurs as a result of a lack of generation in the network.
Underfrequency protection (SAPTUF) measures frequency with high accuracy, and
is used for load shedding systems, remedial action schemes, gas turbine startup and
so on. Separate definite time delays are provided for operate and restore.
SAPTUF is provided with undervoltage blocking.
The operation is based on positive sequence voltage measurement and requires two
phase-phase or three phase-neutral voltages to be connected. For information about
how to connect analog inputs, refer to Application manual/IED application/
Analog inputs/Setting guidelines.
10.1.3 Function block
M13352-3 v6
IEC06000279_2_en.vsd
SAPTUF
U3P*
BLOCK
BLKTRIP
BLKREST
TRIP
START
RESTORE
BLKDMAGN
FREQ
IEC06000279 V2 EN-US
Figure 126: SAPTUF function block
1MRK 505 394-UEN A Section 10
Frequency protection
Line differential protection RED650 2.2 IEC 267
Technical manual