Sel 751A - Figure 2.12 Fiber-Optic Serial, Ethernet, EIA-232 Communication, 4 DO;3 DI;1 AO, and 3 AVI;4 AFDI Voltage Option with Arc-Flash Detector Inputs; Grounding (Earthing) Connections; Power Connections; Serial Ports

2.17
Date Code 20100129 Instruction Manual SEL-751A Relay
Installation
Rear-Panel Connections
Figure 2.12 Fiber-Optic Serial, Ethernet, EIA-232 Communication, 4 DO/3 DI/1AO, and 3 AVI/4 AFDI Voltage
Option With Arc-Flash Detector Inputs
Power Connections
The POWER terminals on the rear panel (A01(+/H) and A02(—/N)) must connect to
110–240 Vac, 110–250 Vdc, or 24–48 Vdc (see Power Supply on page 1.20
for complete power input specifications). The POWER terminals are isolated
from chassis ground. Use 14 AWG (2.5 mm
2
) to 16 AWG (1.5 mm
2
) size wire
to connect to the POWER terminals.
Place an external circuit breaker or switch no more than 3.0 m (9.8 feet) from
the equipment. The circuit breaker (or equivalent approved disconnect device
appropriate for the country of installation) must comply with IEC 60947-1 and
IEC 60947-3 and be identified as the disconnect device for the equipment and
be located near the equipment. This disconnect device must interrupt both the
hot (H) and the neutral (N) power leads.
The maximum current rating for the power disconnect circuit breaker or
overcurrent device (fuse) must be 20 A. An internal power supply fuse
(T 3.15 A H250 V 5 x 20 mm) protects the operational power supply. Be sure
to use fuses that comply with IEC 60127-2.
Grounding (Earthing)
Connections
You must connect the ground terminal labeled GND on the rear panel to a rack
frame or switchgear ground for proper safety and performance. Use 14 AWG
(2.5 mm
2
) wire less than 2 m (6.6 feet) in length for the ground connection.
Serial Ports
Because all ports (F, 2, 3, and 4) are independent, you can communicate to any
combination simultaneously. Although serial Port 4 on the optional
communications card consists of an EIA-485 (4A) and an EIA-232 (4C) port,
only one port is available at a time. Use the Port 4 communications interface
COMMINF setting to select between EIA-485 and EIA-232.
i4317a
i4318a
(A) Rear-Panel Layout (B) Side-Panel Input and Output Designations
Contact with instrument terminals
can cause electrical shock that can
result in injury or death.
!
DANGER
The relay contains devices sensitive
to Electrostatic Discharge (ESD).
When working on the relay with the
front panel removed, work surfaces
and personnel must be properly
grounded or equipment damage may
result.
!
CAUTION