Cisco Systems 3700 Network Router User Manual


 
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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
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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