1-9
Cisco 3700 Series Routers Hardware Installation Guide
OL-2180-08
Chapter 1 Overview of Cisco 3700 Series Routers
Power Supply Options
Power Supply Options
Table 1-3
lists the power supply options supported by Cisco 3700 series routers. Depending on the
configuration specified when you placed your order, your router may not support all of these options.
Internal –48 V Telephony Power Modules
Cisco 3700 series routers provide inline power to IP phones connected to the router through Ethernet
switch network modules. This power is supplied by special –48 V modules that connect directly to the
chassis power supplies in Cisco 3725 and Cisco 3745 routers. A single –48 V power module meets the
power needs of up to 36 IP phones. A Cisco 3745 router with two –48 V power modules installed
provides redundant power for up to 36 IP phones.
Figure 1-5
and
Figure 1-6
show the –48 -V power
modules as they appear when installed in Cisco 3700 series routers.
Table 1-3
Power Supply Options for Cisco 3700 Series Routers
Power Supply Option
Cisco 3725
Cisco 3745
AC input power
Yes
Yes
DC input power
Yes
Yes
–48-V telephony power module to provide inline power to IP phones
Yes
Yes
Dual hot-swappable power supplies
No
Yes
1
1.
Because of increased power consumption in high-temperature environments, a fully loaded Cisco 3745 router requires both
power supplies when ambient temperature exceeds 104°F (40°C). Cisco 3745 routers operating under these conditions do not
support the online replacement of power supplies.
Compatible with Cisco Redundant Power System
Yes
Yes
