Juniper M320 Hardware Manual page 203

Copyright © 2015, Juniper Networks, Inc.
CAUTION: You must ensure that power connections maintain the proper
polarity. The power source cables might be labeled
their polarity. There is no standard color coding for DC power cables. The
color coding used by the external DC power source at your site determines
the color coding for the leads on the power cables that attach to the terminal
studs on each power supply.
To connect the DC source power cables to the router, for each power supply:
Ensure that the voltage across the DC power source cable leads is 0 V and that there
1.
is no chance that the cable leads might become active during installation.
Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect
2.
the strap to an approved site ESD grounding point.
Verify that the source power cabling and the grounding cabling are correct, that they
3.
are not touching or blocking access to router components, and that they do not drape
where people could trip on them.
Switch the circuit breaker on the DC power supply faceplate to the off position (
4.
Remove the clear plastic cover protecting the terminal studs on the faceplate.
5.
Remove the nut and washer from each power terminal stud. If no washers and nuts
6.
are already installed, they should be in the accessory box.
Attach the lugs on the DC source power cables to the terminal studs.
7.
Attach the lugs on the positive (+) DC source power cables to the terminal studs.
a.
Attach the lugs on the negative (–) DC source power cables to the terminal studs.
b.
Secure each cable lug to the terminal stud, first with a washer, then with a nut. Use a
7/16-in. (11 mm) nut driver or wrench to tighten the nut. Apply between 23 lb-in. (2.6
Nm) and 25 lb-in. (2.8 Nm) of torque to each nut.
NOTE: The DC power supplies in slots
by dedicated power feeds derived from feed
in slots
PEM2
derived from feed
A/B feed redundancy for the system.
Loosen the captive screw on the cable restraint on the right edge of the power supply
8.
faceplate.
Route the positive and negative DC power cables through the top and bottom of the
9.
cable restraint.
Tighten the cable restraint captive screw to hold the power cables in place.
10.
PEM0
and must be powered by dedicated power feeds
PEM3
. This configuration provides the commonly deployed
B
Chapter 21: Providing Power to the M320
and to indicate
(+) (–)
and must be powered
PEM1
A , and the DC power supplies
).
O
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