Identification; Functionality; Function Block; Signals - ABB RET650 Technical Manual

1MRK 504 135-UEN A
10.3.1
10.3.2
10.3.3
10.3.4
Technical manual

Identification

Function description
Rate-of-change frequency protection

Functionality

The rate-of-change frequency protection function SAPFRC gives an early indication
of a main disturbance in the system. SAPFRC measures frequency with high
accuracy, and can be used for generation shedding, load shedding and remedial action
schemes. SAPFRC can discriminate between a positive or negative change of
frequency. A definite time delay is provided for operate.
SAPFRC is provided with an undervoltage blocking.

Function block

SAPFRC
U3P* TRIP
BLOCK START
RESTORE
BLKDMAGN
IEC09000281_1_en.vsd
IEC09000281 V1 EN
Figure 108: SAPFRC function block

Signals

Table 164: SAPFRC Input signals
Name Type
U3P GROUP
SIGNAL
BLOCK BOOLEAN
Table 165: SAPFRC Output signals
Name Type
TRIP BOOLEAN
START BOOLEAN
RESTORE BOOLEAN
BLKDMAGN BOOLEAN
Frequency protection
IEC 61850 IEC 60617
identification identification
SAPFRC
df/dt > <
SYMBOL-N V1 EN
Default Description
- Three phase group signal for voltage inputs
0 Block of function
Description
Operate/trip signal for frequency gradient
Start/pick-up signal for frequency gradient
Restore signal for load restoring purposes
Blocking indication due to low amplitude
Section 10
ANSI/IEEE C37.2
device number
81
239