Cisco Systems OL-14587-01 manual Power Outage, Power Guidelines

Chapter 2 Preparing to Install the Cisco Unified IP Phone on Your Network

Providing Power to the Phone

Power Outage

Your accessibility to emergency service through the phone is dependent on the phone being powered. If there is an interruption in the power supply, Service and Emergency Calling Service dialing will not function until power is restored. In the case of a power failure or disruption, you may need to reset or reconfigure equipment before using the Service or Emergency Calling Service dialing.

Power Guidelines

Table 2-1provides guidelines that apply to external power and to PoE power for the Cisco Unified IP Phones 7931G.

Table 2-1	Guidelines for Powering the Cisco Unified IP Phones 7931G
Power Type		Guidelines
External power—		The CP-PWR-CUBE-3 external power supply may be used with the
Provided through a Cisco		Cisco Unified IP Phones 7931G.
external power supply.
External power—		The Cisco Unified IP Phone Power Injector may be used with any
Provided through the		Cisco Unified IP Phone. Functioning as a midspan device, the injector
Cisco Unified IP Phone		delivers inline power to the attached phone. The Cisco Unified IP Phone
Power Injector.		Power Injector is connected between a switch port and the IP Phone, and
		supports a maximum cable length of 100m between the unpowered switch
		and the phone.
PoE power—Provided by		• The Cisco Unified IP Phones 7931G supports IEEE 802.3af Power
a switch through the		over Ethernet.
Ethernet cable attached to		• To ensure uninterruptible operation of the phone, make sure that the
the phone.
		switch has a backup power supply.
		• Make sure that the CatOS or IOS version running on your switch
		supports your intended phone deployment. Refer to the documentation
		for your switch for operating system version information.

	Cisco Unified IP Phone 7931G Administration Guide for Cisco Unified Communications Manager 6.1
OL-14587-01		2-5