Juniper QFX5100, Hardware Manual

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7.
Connect each power supply to the power sources. Secure power source cables to the
power supplies by screwing the ring lugs attached to the cables to the appropriate
terminals by using the screw from the terminals (see
Figure 42 on page 179 and
Figure 43 on page 179 ).
CAUTION: The DC 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. The same polarity terminal can be wired together from the
same source to provide an additional current path in a higher power
chassis. Do not connect the terminals to different sources. For example,
connect –48 V from DC source feed A to the input terminals of one power
supply and connect –48 V from feed B to the input terminals of the second
power supply on the other side of the chassis. This configuration provides
the commonly deployed A/B feed redundancy for the system.
a.
Secure the ring lug of the positive (+) DC power source cable to the V+ terminal
on the DC power supply.
b.
Secure the ring lug of the negative (–) DC power source cable to the V– terminal
on the DC power supply.
c.
Tighten the screws on the power supply terminals until snug using the screwdriver.
Do not overtighten—apply between 5 in-lb (0.56 Nm) and 6 in-lb (0.68 Nm) of
torque to the screws.
Copyright © 2014, Juniper Networks, Inc. 178
QFX5100 Switch Hardware Guide