Phone Power Requirements - Cisco 7800 Series Administration Manual

Phone Power Requirements

Pin Number
7
8
Note
Phone Power Requirements
The Cisco IP Phone can be powered with external power or with Power over Ethernet (PoE). A separate power
supply provides external power. The switch can provide PoE through the phone Ethernet cable.
Note When you install a phone that is powered with external power, connect the power supply to the phone and to
a power outlet before you connect the Ethernet cable to the phone. When you remove a phone that is powered
with external power, disconnect the Ethernet cable from the phone before you disconnect the power supply.
Table 11: Guidelines for Cisco IP Phone Power
Power Type
External power: Provided through the
CP-PWR-CUBE-3= external power supply
External power—Provided through the Cisco IP Phone
Power Injector
PoE power—Provided by a switch through the
Ethernet cable attached to the phone.
The documents in the following table provide more information on the following topics:
• Cisco switches that work with Cisco IP Phones
• Cisco IOS releases that support bidirectional power negotiation
Cisco IP Phone 7800 Series Administration Guide for Cisco Unified Communications Manager
10
BI stands for bidirectional, while DA, DB, DC, and DD stand for Data A, Data B, Data C, and
Data D respectively.
Function
BI_DC+
BI_DC-
Guidelines
The Cisco IP Phone uses the CP-PWR-CUBE-3 power
supply.
The Cisco IP Phone Power Injector may be used with
most Cisco IP Phones. The phone datasheet identifies
if the phone can use the power injector.
Functioning as a midspan device, the injector delivers
inline power to the attached phone. The Cisco IP
Phone Power Injector connects between a switch port
and the IP Phone, and supports a maximum cable
length of 100m between the unpowered switch and
the IP phone.
To ensure uninterruptible operation of the phone,
make sure that the switch has a backup power supply.
Make sure that the CatOS or IOS version that runs on
your switch supports your intended phone deployment.
See the documentation for your switch for operating
system version information.
About the Cisco IP Phone