Installing An M320 Dc Power Supply - Juniper M320 Hardware Manual

Copyright © 2010, Juniper Networks, Inc.

Installing an M320 DC Power Supply

To install a DC power supply (see Figure 105 on page 200):
Make sure that the voltage across the DC power source cable leads is 0 V and that
1.
there is no chance that the cables might become active during installation.
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.
Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect
2.
the strap to one of the ESD points on the chassis.
Switch the circuit breaker on the DC power supply faceplate to the off position (
3.
Using both hands, slide the power supply into the chassis until you feel resistance.
4.
Firmly push the power supply into the chassis until it comes to a stop. The power
5.
supply faceplate should be flush with any adjacent power supply faceplates.
Tighten the captive screws on each side of the power supply faceplate to secure the
6.
power supply in the chassis.
Remove the clear plastic cover protecting the terminal studs on the faceplate.
7.
Remove the nuts and washers from the terminal studs.
8.
Attach the lugs on the DC source power cables to the terminal studs.
9.
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 socket 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
feed redundancy for the system.
A/B
Loosen the captive screw on the cable restraint on the right edge of the power supply
10.
faceplate.
Route the positive and negative DC power cables through the top and bottom of the
11.
cable restraint.
Chapter 13: Replacing the M320 Router Hardware Components
PEM0
and PEM3 must be powered by dedicated power feeds
. This configuration provides the commonly deployed
B
and to indicate
(+) (–)
O
and must be powered
PEM1
, and the DC power supplies
A
).
199