Juniper ACX5448-D Hardware Manual page 101

CAUTION:
attach a cable lug to the grounding and power cables that you supply. A cable with
an incorrectly attached lug can damage the router (for example, by causing a short
circuit).
To meet safety and electromagnetic interference (EMI) requirements and to ensure
proper operation, you must connect the chassis to earth ground before you connect
it to power. For installations that require a separate grounding conductor to the
chassis, use the protective earthing terminal on the router chassis to connect to
the earth ground. .
Install the PSM in the chassis.
Ensure that you have the following parts and tools available:
DC power source cables 12 AWG with ring lug (Molex 190700069 or equivalent)(not provided)
Phillips (+) screwdriver, number 2 (not provided)
Multimeter (not provided)
To connect DC power to an ACX5400 router:
1. Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other
end of the strap to the ESD point on the chassis.
2. Verify that the DC power cables are correctly labeled before making connections to 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 the resistance of the –48V and RTN DC cables to chassis
ground:
The cable with very low resistance (indicating a closed circuit) to chassis ground is positive (+). You
install this cable on the V+ (return) DC power input terminal.
The cable with very high resistance (indicating an open circuit) to chassis ground is negative (–). You
install this cable on the V– (input) DC power input terminal.
CAUTION:
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 DC power input terminals
on each PSM.
Before you connect power to the router, a licensed electrician must
You must ensure that power connections maintain the proper
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