Routers Hardware Installation Guide

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Cisco 3700 Series Routers Hardware Installation Guide
OL-2180-08
Chapter 3 Installing the Router
Power Connections
Figure 3-17 DC Wire Routing and Attachment for Cisco 3725
Approved Scenarios and Scenarios Not Approved for Dual DC Power Supply Configuration in Cisco 3725 Routers
You can connect a single DC power source to either the A input or the B input. If there are dual power
sources, connect one source to the A input and one source to the B input. Both sources must be the same
polarity (with respect to ground) and voltage (within 0.25 volts). Do not connect –DC grounded and +DC
grounded dual sources to a Cisco 3725 router.
Caution Dual sources with opposite-polarity grounding can damage equipment.
In Figure 3-18, either the positive source terminal or the negative source terminal is tied to ground
.
Figure 3-18 Connecting to One Source Only—Source A or Source B
88035
AL
CD
LP
BEFORE INSTALLATION
DSU
56K
SEE MANUAL BEFORE INSTALLATION
Cable tie
From DC
power
source
Plastic cover
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B+
B-
+
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