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Cisco 12016, Cisco 12416, and Cisco 12816 Router Installation and Configuration Guide
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Chapter 3 Installing the Router
Connecting Power to the Power Shelf
Because there is no color code standard for source DC wiring, you must be sure
that power source cables are connected to the power shelf with the proper
positive (+) and negative (–) polarity:
•
In some cases, the source DC cable leads might have a positive (+) or a
negative (–) label. This is a relatively safe indication of the polarity,
but you
must verify the polarity by measuring the voltage between the DC cable leads
.
Be sure that the positive (+) and negative (–) cable leads match the positive
(+) and negative (–) labels on the power shelf when making the measurement.
•
A green (or green and yellow) cable typically indicate that it is a ground
cable.
Caution
DC PEMs contain circuitry to trip the breaker on the PEM if the PEM detects a
reverse polarity condition. No damage should occur from reverse polarity, but you
should correct a reverse polarity condition immediately.
Note
The length of the cables depends on the location of your router in relation to the
source of DC power. These cables and the cable lugs used to attach the cables to
the router chassis are not available from Cisco Systems. They are available from
any commercial cable vendor. For more information on site power and source DC
cable requirements, see the
“Power Connection Guidelines” section on page 2-17
.
Warning
To ensure that power remains off while you are performing this procedure, tape
the DC circuit breaker switch in the off (0) position.
Use the following procedure to connect DC power cables to the power shelf.
Step 1
Remove the cover over the cable terminal studs on the back panel of the power
shelf (
Figure 3-23
):
a.
Loosen (but do not remove) the screw that secures the cover.
b.
Slide the cover down then pull the cover over the screw head and away from
the PEM shelf.