Function Block - ABB REL 551-C1*2.5 Technical Reference Manual

1.3
58
Line differential protection, phase segregated
(DIFL)

Function block

DIFL-
DIFFERENTIAL
BLOCK TRIP
RTCREC2
CTSUP
RTCREC1
RTCSEND2
CTSAT
RTCSEND1
COMOK
COMFAIL
en03000099.vsd
Figure 16: DIFL function block for three phase tripping.
DIFL-
DIFFERENTIAL
BLOCK TRIP
CTSUP TRL1
RTCSEND2 TRL2
RTCSEND1 TRL3
RTCREC2
RTCREC1
CTSAT
COMOK
COMFAIL
xx00000689.vsd
Figure 17: DIFL function block for single two and/or three phase tripping.
Chapter 4
Line differential protection