Removing A T640 Dc Power Supply Cable From A Two-Input 160-A Power Supply, Three-Input 240-A Dc Power Supply, Or A Four-Input 240-A Dc Power Supply - Juniper T640 Hardware Manual

Copyright © 2013, Juniper Networks, Inc.
Removing a T640 DC Power Supply Cable from a Two-Input 160-A Power Supply,
Three-Input 240-A DC Power Supply, or a Four-Input 240-A DC Power Supply
To remove a DC power supply cable:
Locate a replacement power cable that meets the specifications required for the
1.
power supply.
CAUTION: A licensed electrician must attach a cable lug to the power
cable that you supply. A cable with an incorrectly attached lug can damage
the router.
Turn off the customer site circuit breaker that provides voltage to the DC power cable
2.
being replaced. Make sure that the voltage across the DC power source cable leads
is 0 V and that there is no chance that the cables might become active during the
removal process. Follow your site's safety and ESD procedures.
Remove the power cable from external DC power source.
3.
Attach an electrostatic discharge (ESD) grounding strap to your bare wrist, and connect
4.
the strap to one of the ESD points on the chassis.
Switch the circuit breakers on the power supply faceplate to the off position (
5.
Remove the clear plastic cover protecting the terminal studs on the faceplate.
6.
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.
Remove the nut and washer from the terminal stud. Use a 7/16-in. (11 mm) nut driver.
7.
Remove the cable lug from the terminal studs.
8.
Loosen the captive screw or screws on the cable restraint on the right edge of the
9.
power supply faceplate.
Carefully move the power cable out of the way.
10.
Figure 199 on page 336, Figure 200 on page
remove the nut and washer from the terminal stud.
Chapter 17: Replacing T640 Router Hardware Components
336, and Figure 201 on page 337
).
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and to indicate
(+) (–)
show how to
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