2.18
SEL-787 Relay Instruction Manual Date Code 20081022
Installation
AC/DC Control Connection Diagrams
Voltage Connections
With the voltage inputs option, the AC voltages may be directly connected,
wye-wye VT connected, open-delta VT connected, or a single-phase VT can
be used. Figure 2.16 and Figure 2.17 show the methods of connecting single-
phase and three-phase voltages.
Figure 2.16 Single-Phase Voltage Connections
NOTE: Current limiting fuses in
direct-connected voltage applications
are recommended to limit short circuit
arc flash incident energy.
AB
C
EO1
EO2
EO3
EO4
Single Phase-to-Neutral VT Connection
Single Phase-to-Phase VT Connection
SEL-787
F1
AB
C
EO1
EO2
EO3
EO4
SEL-787
F1
Note: The VT secondary circuit must be grounded in the relay cabinet.