Figure 23: Dc Power Supply Faceplate For A Qfx5200 - Juniper QFX5200 Hardware Manual

QFX5200 Switch Hardware Guide
70
(B) to the second power supply. This configuration provides the commonly deployed
A/B feed redundancy for the system.
The terminal block of the power supply has four terminals labeled V+, V+, V–, and V–
for connecting DC power source cables labeled positive (+) and negative (–). The V+
terminals are shunted internally together, as are the V- terminals.
CAUTION: The connection between each power source and power supply
must include a circuit breaker.
Do not connect two sources to a single power supply because doing so
can potentially cause circulating current in feed wires whenever there is
any difference in the voltage of the two sources.
Secure the ring lug of the positive (+) DC power source cable to the V+ terminal
a.
on the DC power supply.
Secure the ring lug of the negative (–) DC power source cable to the V– terminal
b.
on the DC power supply.
Tighten the screws on the power supply terminals until snug using the screwdriver.
c.
Do not overtighten—apply between 5 in-lb (0.56 Nm) and 6 in-lb (0.68 Nm) of
torque to the screws.

Figure 23: DC Power Supply Faceplate for a QFX5200

1— Shunt negative input terminals (+RTN)
2— Shunt positive input terminals (-48V)
3— Terminal block
4— Ejector lever
5
5— ESD grounding point
6— Fault LED
7— Output LED
8— Input LED
Copyright © 2017, Juniper Networks, Inc.