2.27
Date Code 20100129 Instruction Manual SEL-751A Relay
Installation
AC/DC Control Connection Diagrams
Voltage option is needed for voltage elements and metering (e.g., voltage, KW, KVAR). INxxx and OUTxxx indicate user-
configurable optional digital inputs and outputs.
Figure 2.23 SEL-751A Provides Overcurrent Protection for a Transformer Bank With a
Tertiary Winding (Wye-Connected PTs)
TC
Trip
Coil
52A
(+)
(—)
Trip
Circuit
IA
C
B
A
SEL-751A RELAY
OUT103
CC
Close
Coil
52B
(+)
(—)
Close
Circuit
IB OUT102
86
Lock
Out
86B
(+)
(—)
Breaker
Failure
Trip
Circuit
IC OUTxxx
IN
(+)
52A
to Annunciator, RTU,
or SEL-2032/2030/2020
ALARM
OUT101
(+)
(—)
Breaker Status
INxxx
n
a
(Low-Side)
(Tertiary)
cb
N
52
VCNVBVA