Mitel MiVOICE BUSINESS, Инструкция по инженерии

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Engineering Guidelines
96
IN-LINE ETHERNET AC POWER ADAPTERS
A special In-Line Ethernet power adapter can provide local power feed to a wide range of
MiVoice IP Phones. Refer to Table 32 for details on which models support this powering option.
The power adapter plugs into a standard AC power outlet and has two RJ-45 connections, one
connecting to the network, and the other to the phone with power feed. Available units are
• 500002070 - 48 VDC Ethernet Power Adapter NA 120 V 50-60 Hz
• 500002080 - 48 VDC Ethernet Power Adapter UK 240 V 50 Hz
• 500002090 - 48 VDC Ethernet Power Adapter Europe 240 V 50 Hz.
IN-LINE GIGABIT ETHERNET AC POWER ADAPTERS
If the installer chooses to power the 5360 phone with a local in-line AC adapter, then the following
adapter must be used as it is the only adapter approved for use with the 5360 phone.
• 51015131: 802.3af 48VDC Gb Ethernet Power Adapter Universal, 100-240V 50-60 Hz
802.3AF POWERING
Power over Ethernet technology allows devices such as IP Phones to receive power as well
as data over an existing Ethernet LAN infrastructure. The standard for Power over Ethernet is
IEEE 802.3af, and Mitel 5xxx series IP Phones conform to this standard.
There are two methods of providing power in the standard:
• “Phantom” power across existing Ethernet wires (RJ-45 pins 1, 2, 3 and 6). This is the
method typically used by 802.3af compliant Ethernet switches. The 3300 CXi controller
uses the phantom (signal pair) method for delivering power.
• “Spare pair” power where power is supplied across RJ-45 pins 4, 5, 7 and 8. This is the
method typically used by mid-span devices that sit between a non- 802.3af Ethernet switch
and the end device.
Devices that provide power by either method are called are called “Power Sourcing Equipment”
(PSE) and devices that accept the power are “Powered Devices” (PD). MiVoice IP Phones are
Powered Devices. Some Mitel phones also accept local powering options. For more information,
see Table 32, “IP Phone Power Options,” on page 94.
The standard requires that a “signature” be detected on an PSE port prior to applying significant
power on the cable. Regular PC NICs do not have this signature, whereas MiVoice IP Phones do.
A Power over Ethernet port produces current limited, low voltage pulses which allow it to probe
for a particular impedance at the end of the Ethernet cable. If this “signature” is detected (an
IP Phone, for example), then the PSE assumes that power is required. If the “signature” is not
detected (e.g. PC NIC), then the PSE does not apply power.
Note: Ensure that the Ethernet power adapter and its associated IP phone are
co-located.
Note: Mitel phones can be powered from equipment that uses phantom powering or
spare pair powering.