Juniper T640 Hardware Manual page 191

Copyright © 2013, Juniper Networks, Inc.
CAUTION: All connected inputs on the DC power supply in slot PEM0 must
be powered by dedicated power feeds derived from feed A, and all connected
inputs on the DC power supply in slot PEM1 must be powered by dedicated
power feeds derived from feed B. This configuration provides the commonly
deployed A/B feed redundancy for the system.
CAUTION: You must use an appropriate torque-controlled tool to tighten
the nuts. Applying excessive torque damages the terminal studs and the
power supply. The absolute maximum torque that may be applied to this nut
is 45 lb-in. (5.0 Nm).
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.
NOTE: Both DC power supplies (PEM 0 and PEM 1) must be cabled and
configured exactly the same. The DC power cables must be connected to
the same input terminals on each power supply.
To connect four 60-A DC source power cables to the router, follow this procedure for
each DC power supply:
Switch off the customer site circuit breakers. Ensure that the voltage across the DC
1.
power source cable leads is 0 V and that there is no chance that the cable leads might
become active during installation.
Verify that a licensed electrician has attached the cable lugs provided with the router
2.
to the power cables. See the DC power cable and lug specifications for your router
for more information.
Switch the power switch on the power supply faceplate to the standby position.
3.
Remove the clear plastic cover protecting the terminal studs on the faceplate.
4.
Remove the nut and washer from each power terminal stud to be connected (
5.
, , ,
0 INPUT 1 INPUT 3 INPUT 4
nuts are already installed, they should be in the accessory box.
Remove the captive screws on the smallest cable restraint on the right edge of the
6.
power supply faceplate, and the largest cable restraint to the left (using a Phillips (+)
screwdriver, number 2).
Chapter 13: Providing Power to the T640 Router
, and , , , and
RTN 0 RTN 1 RTN 3
(+) and (–) to indicate
INPUT
). If no washers and
RTN 4
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