Cisco Systems 7970G manual Power Guidelines, Phone Power Consumption and Display Brightness

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

Providing Power to the Phone

Power Guidelines

	Table 2-1provides guidelines that apply to external power and to inline power
	power for phones the Cisco Unified IP Phones 7970G/7971G-GE.
Table 2-1	Guidelines for Powering the Cisco Unified IP Phones 7970G/7971G-GE
Power Type		Guidelines
External power—		The Cisco Unified IP Phones 7970G/7971G-GE use the CP-PWR-CUBE-3
Provided through the		power supply.
CP-PWR-CUBE-3
external power supply
External power—		The Cisco Unified IP Phone Power Injector may be used with any Cisco
Provided through the		Unified IP Phone. Functioning as a midspan device, the injector delivers
Cisco Unified IP Phone		inline power to the attached phone. The Cisco Unified IP Phone Power
Power Injector		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
		IP Phone.
PoE power—Provided by		• The inline power patch panel WS-PWR-PANEL is not compatible
a switch through the		with the Cisco Unified IP Phones 7970G/7971G-GE.
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.

Phone Power Consumption and Display Brightness

The power consumed by a phone depends on its power configuration. See Table 2-1for a power configuration overview. See Table 2-2for the maximum power consumed by a phone for each configuration option and the correlating phone screen brightness level.

Note Power consumption values shown in the table include power losses in the cable that connects the phone to the switch.

Cisco Unified IP Phone Administration Guide for Cisco Unified CallManager 5.1 (SIP), Cisco Unified IP Phones

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