Connecting The Dc Power Cables - Juniper T640 Quick Start Manual

Copyright © 2015, Juniper Networks, Inc.

Connecting the DC Power Cables

To connect DC power cables to the router:
Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect
1.
the strap to an approved site ESD grounding point. See the instructions for your site.
Switch off the customer site circuit breakers. Make sure that the voltage across the
2.
DC power source cable leads is 0 V and that there is no chance that the cable leads
might become active during installation. Follow your site's instructions for safety.
Verify that a licensed electrician has attached the cable lugs provided with the router
3.
to the DC power cables.
Verify that the router is properly grounded.
4.
Detach the ESD grounding strap from the approved site ESD grounding point, and
5.
connect the strap to one of the ESD points on the chassis.
Verify that the circuit breakers on the power supply faceplate are in the
6.
position.
Remove the clear plastic cover protecting the terminal studs on the power supply
7.
faceplate.
Remove the nut and washer from the power terminal studs for
8.
NOTE: For a three-input 240-A DC power supply,
for the router and should not be connected.
Attach each power cable lug to the correct terminal stud on the power supply
9.
faceplate, and secure the cable lug first with washer, then with the 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. (See
or Figure 15 on page 30.
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 in-lb (5.0 Nm).
Attach and secure the positive (+) cable lugs to the
a.
Attach and secure the negative (–) cable lugs to the
b.
Verify that the positive and negative power cables are connected to the correct terminal
10.
studs.
Route the DC power cables through the cable restraint or restraints.
11.
Tighten the cable restraint captive screw or screws to hold the power cables in place.
12.
Connecting the DC Power Cables
INPUT O
is not supported
INPUT 2
Figure 10 on page 23, Figure 14 on page
terminals.
RTN (return)
-48V (input) terminals.
OFF (O)
and INPUT 1 .
28,
27