Juniper EX9214 Hardware Manual page 184

EX9214 Switch Hardware Guide
160
On the power supply, rotate the metal cover away from the input mode switch to
3.
expose the switch.
Move the input mode switch to position
4.
NOTE: For a fully redundant configuration in two-feed mode, sixteen feeds
are required.
Set the power switch of the power supply to the OFF
5.
Verify that the power cables are labeled before making connections to the power
6.
supply. In a typical power distribution scheme where the return (RTN) is connected
to chassis ground at the battery plant, you can use a multimeter to verify the resistance
of the –48 V and RTN DC cables to chassis ground.
Cable with large resistance (indicating an open circuit) to chassis ground is –48 V.
Cable with low resistance (indicating a closed circuit) to chassis ground is RTN.
CAUTION: You must ensure that power connections maintain the proper
polarity. The power source cables might be labeled (+) and (–) to indicate
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 clear plastic cover from the terminal studs on the faceplate and remove
7.
the nut and washer from each of the terminal studs.
Secure each power cable lug to the terminal studs, first with the flat washer, then
8.
wish the split washer, and then with the nut. Apply between 23 lb-in (2.6 Nm) and 25
lb-in (2.8 Nm) of torque to each nut. Do not overtighten the nut. (Use a 7/16 in. [11 mm]
torque-controlled driver or socket wrench.) See
On , attach the positive (+) DC power source cable lug to the
INP0
terminal. Repeat this step for
On , attach the negative (–) DC power source cable lug to the
INP0
terminal. Repeat this step for
CAUTION: Ensure that each power cable lug seats flush against the surface
of the terminal block as you are tightening the nuts. Ensure that each nut
is properly threaded onto the terminal stud. You must be able to spin the
nuts freely with your fingers when they are placed onto the terminal stud
0 for one feed or position
position.
(0)
Figure 51 on page
INP1 if you are using two feeds.
INP1 if you are using two feeds.
Copyright © 2017, Juniper Networks, Inc.
1 for two feeds.
162.
(return)
RTN
(input)
–48 V