Juniper SRX1400 Hardware Manual page 101

Copyright © 2011, Juniper Networks, Inc.
Chapter 9: Grounding and Providing Power to the SRX1400 Services Gateway
WARNING: Before performing the following procedure, ensure that power is
removed from the DC circuit. To ensure that all power is off, locate the circuit
breaker on the panel board that services the DC circuit, switch the circuit
breaker to the off position, and tape the switch handle of the circuit breaker
in the off position.
You connect DC power to the device by attaching power cables from the external DC
power sources to the terminal studs on the power supply faceplates.
CAUTION: Before you connect power to the services gateway, a licensed
electrician must attach a cable lug to the grounding and power cables that
you use. A cable with an incorrectly attached lug can damage the device (for
example, by causing a short circuit). To meet safety and electromagnetic
interference (EMI) requirements and to ensure proper operation, you must
connect the SRX1400 Services Gateway to ground before you connect it to
power.
To connect the DC source power cables to the device for each power supply:
Switch off the dedicated facility circuit breakers. Ensure that the voltage across the
1.
DC power source cable leads is 0 V and that there is no chance that the cable leads
might become active during installation.
Remove the clear plastic cover protecting the terminal studs on the faceplate.
2.
Verify that the DC power cables are correctly labeled before making connections to
3.
the power supply.
In a typical power distribution scheme where the return is connected to chassis ground
at the battery plant, you can use a multimeter to verify that the ohm output of the
and DC cables to chassis ground. The cable with very large resistance
-48V RTN
(indicating an open circuit) to chassis ground will be
low resistance (indicating a closed circuit) to chassis ground will be
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 screws and square washers from the terminals, using a Phillips (+)
4.
screwdriver, number 2.
Secure each power cable lug to the terminals with the square washers and the screws.
5.
Apply between 23 in.-lb (2.6 Nm) and 25 in.-lb (2.8 Nm) of torque to each screw.
-48V , and the cable with very
.
RTN
and to indicate
(+) (–)
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