ABB REL650 - Page 69

Z 1 = R 1 + jX 1
Z 0 = R 0 + jX0
A B
Zone 1
Zone 2
C
Zone 1
Zone 2
Communication
Y
Y
REL 650
REL650
ANSI11000250-1-en.vsd
Delta based fault
inception detection and
forward fault inhibit
Delta based fault
inception detection and
forward fault inhibit
ANSI11000250 V1 EN
Figure 18: Principle of delta blocking communication scheme
When a communication signal is received (CR) the overeaching zone (zone2) is blocked.
The logic is shown in figure 19.
Receive signal (CR)
Trip
Send signal (CS)
Zone 1 TRIP
Zone 1 PICKUP
Zone 2 TRIP
Zone 2
PICKUP
ZQMPDIS (21)
OR
AND
CS
Delta based fault
inception detection
ZCPSCH (85)
ANSI11000251-1-en.vsd
AND
ANSI11000251 V1 EN
Figure 19: Logic of delta blocking communication scheme
1MRK 506 334-UUS A Section 3
REL650 setting examples
63
Application manual