Juniper T640 Hardware Manual page 271

Copyright © 2017, Juniper Networks, Inc.
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).
Route the negative (–) DC source power cables for
7.
, over the smallest cable restraint on the far right. The cable restraint is marked
INPUT 4
as follows top to bottom:
NOTE: You must route the cables in the locations as marked to be able
to replace the clear plastic cover over the terminal studs.
Attach the negative (–) DC source power cable lugs to the –48V (input) terminals
on the right: ,
INPUT 0 INPUT 1
terminal studs, first with the washers, then with the nuts. Using a 7/16-in. (11 mm) nut
driver, tighten the nuts. Apply between 23 lb-in. (2.6 Nm) and 25 lb-in. (2.8 Nm) of
torque to each nut.
Chapter 22: Providing Power to the T640
, and , ,
RTN 0 RTN 1 RTN 3
INPUT 0
INPUT 0 , INPUT 1 , INPUT 3
, , and
INPUT 3 INPUT 4
, and ). If no washers and
RTN 4
, , , and
INPUT 1 INPUT 3
, and INPUT 4 .
. Secure the cable lugs to the
INPUT
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