Cisco 3700 Series Hardware Installation Manual page 63

Chapter 3 Installing the Router
Figure 3-20
In Figure
Caution
configuration.
Figure 3-21
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.
OL-2180-08
Connecting Source A and Source B with Common Positive Terminals
Va voltage = Vb voltage (within 0.25 V)
A-
Va
+
A+
B+
+
Vb
B-
3-21, source A and source B are wired with opposite polarity grounds. Do not use this DC input
Source A and Source B Wired with Opposite-Polarity Grounds
Va Va
+ +
+ +
Vb Vb
Va voltage = Vb voltage (greater than 0.25 V)
+ +
+ +
A- A-
A+ A+
B+ B+
B- B-
Cisco 3700 Series Routers Hardware Installation Guide
Power Connections
A- A-
Va Va
A+ A+
B+ B+
Vb Vb
B- B-
3-17