ABB REL650 Applications Manual page 67

1MRK 506 334-UUS A
Application manual
Zone 4 ( reverse )
A
REL 650
Y
ANSI11000112 V1 EN
Figure 16: Principle of blocking communication scheme
A communication signal is sent (CS) if a fault is detected by zone 4 (reverse zone). When
a communication signal is received (CR) the fast zone 2 is blocked. The logic is shown in
figure 17.
Zone 2
Zone 1
Z 1 = R 1 + jX 1
Z 0 = R 0 + jX0
Communication
Zone 1
Zone 2
Section 3
REL650 setting examples
B
REL 650
C
Y
Zone 4 ( reverse )
ANSI11000112_1_en.vsd
61