Sel 551 - Figure 2.10 SEL-551 Provides Overcurrent Protection for an Industrial Distribution Feeder (Core-Balance Current Transformer Connected to Current Input Channel IN)

2.10
SEL-551 Relay Instruction Manual Date Code 20110408
Installation
SEL-551 AC/DC Connection Diagrams for Example Applications
A
Figure 2.10 SEL-551 Provides Overcurrent Protection for an Industrial Distribution Feeder (Core-Balance
Current Transformer Connected to Current Input Channel IN)
A core-balance current transformer is often referred to as a zero-sequence,
ground fault, or window current transformer.
52A
C
B
A
TC
52
(-)
Trip
Circuit
Breaker
Failure
Trip
Circuit
to Annunciator or RTU
Trip
Coil
(+)
(+)
(+)
86B
Out
Lock
86
(-)
SEL-551 Relay
IN
IC
IB
IA
IN2
IN1
ALARM
OUT4
OUT3
OUT2
OUT1
N