Cisco 3900 series User Manual

3-19
Cisco 2900 and 3900 Series Hardware Installation
OL-18712-01
Chapter 3 Installing and Connecting the Router
Connecting Power
Warning This product relies on the building’s installation for short-circuit (overcurrent) protection. Ensure that
the protective device is rated not greater than:
15A, 120VAC (16A, 240VAC). Statement 1005
Connecting to DC Power
If your router has a DC-input power supply, follow the directions in this section for proper wiring. A
router with a DC-input power supply has a terminal block for the DC power connections. If backup
power is required, see the “Connecting to Backup Power” section.
• DC Wiring Requirements for Cisco 2911, 2921, and 2951 Routers, page 3-19
• Wiring Procedure for DC Input on Cisco 2911, 2921, and 2951 Routers, page 3-20
• Approved Scenarios and Scenarios Not Approved for Dual DC Power Supply Configuration on
Cisco 2911, 2921, and 2951 Routers, page 3-23
• DC Wiring Requirements for Cisco 3900 Series Routers, page 3-24
Caution DC return is isolated from the frame. (NEBS DC-I)
Warning This product requires short-circuit (overcurrent) protection, to be provided as part of the building
installation. Install only in accordance with national and local wiring regulations. Statement 1045
Warning This product relies on the building's installation for short-circuit (overcurrent) protection. Ensure that
the protective device is rated not greater than:
60 VDC, 20 A.
Statement 1005
Warning Only trained and qualified personnel should be allowed to install, replace, or service this equipment.
Statement 1030
Warning Use copper conductors only. Statement 1025
DC Wiring Requirements for Cisco 2911, 2921, and 2951 Routers
A Cisco 2911, Cisco 2921, or Cisco 2951 router with a DC-input power supply requires copper wire and
crimp-type terminals for the power connections. Table 3-1 and Table 3-2 summarize the wiring
requirements.
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 and voltage.

Cisco 3900 series Specifications

General

Brand	Cisco
Model	3900 series
Category	Network Router
Language	English