3-17
Cisco 3700 Series Routers Hardware Installation Guide
OL-2180-08
Chapter 3 Installing the Router
Power Connections
Figure 3-20
Connecting Source A and Source B with Common Positive Terminals
Caution
In
Figure 3-21
, source A and source B are wired with opposite polarity grounds.
Do not
use this DC input
configuration.
Figure 3-21
Source A and Source B Wired with Opposite-Polarity Grounds
Wiring the DC-Input Power Supply in Cisco 3745 Routers
If your Cisco 3745 router has a DC-input power supply, follow the directions in this section for proper
wiring.
A-
A+
B+
B-
Va
Vb
+
+
127040
A-
A+
B+
B-
Va
Vb
+
+
A-
Va voltage = Vb voltage (within 0.25 V)
Va voltage = Vb voltage (greater than 0.25 V)
A+
B+
B-
Va
Vb
+
+
A-
127041
A+
B+
B-
Va
Vb
+
+
A-
A+
B+
B-
Va
Vb
+
+