User's Manual

Table Of Contents
c02.fm
Overview
DECT IP Base Station Data
A31003-C1010-S100-2-7620, 08/2010
HiPath Cordless IP, Service Manual 27
2.3.2 Powering the DECT IP Base Stations
The DECT IP base station can be powered in two different ways:
Power-over-Ethernet (PoE) Class 2 to 802.3af
Power-over-Ethernet: PoE injectors
A PoE injector is used if PoE cannot be made available in the network. The
PoE injector must be 802.3af-compatible. Pre-tested and released PoE
injectors are available as optional features within the scope of the HiPath
Cordless IP solution.
The IEEE802.3af standard allows the PoE Injector to be in any location
between the switch and the BSIP1. The maximum allowed distance between
the switch and the BSIP1 for IEEE802.3 compliance is 100 m. It is typical to
deploy the PoE Injector close to the switch, since by doing this one can use
a single UPS (central power supply) to backup both the switch and the PoE
Injector.
If overall efficiency is more important than centralized backup and/or
management, it makes sense to place the PoE Injector closer to the BSIP1,
since the power dissipated at the cable between the PoE Injector and the
BSIP1 is directly proportional to the length of this cable (P = I
2
* R).
Figure 8 PoE Injector