User's Manual

Table Of Contents
10 System Description
Chapter 1 - System Description
1.2.7 Power Interface Unit (PIU)
The single Euro PIU module is the interface between the Base
Station site's DC power source and the Base Station chassis PSUs
and external AU ODUs, which receive power via the AU-IDUs.
The PIU filters and stabilizes the Base Station input power and
protects the system from power problems such as over voltage,
surge pulses, reverse polarity connection and short circuits. It also
filters high frequency interference (radiated emissions) and low
frequency interference (conducted emissions) to the external power
source. Each Base Station chassis contains two slots for an optional
1+1 PIU redundancy. One PIU is sufficient to support a fully
populated chassis. Two PIU modules provide redundant power feeding (two input
sources) while avoiding current flow between the two input sources.
1.2.8 Power Supply Unit (PSU)
The single Euro PSU module is a 48 VDC power supply unit. Each
Base Station chassis can contain up to four PSU modules providing
N+1 redundancy configurations.
Table 1-2 displays the number of PSU modules (excluding
redundant units) required for various Base Station configurations
without NPU redundancy (one NPU):
Table 1-1: Number of AU-IDUs, AU-ODUs and Power Feeders Required for Various Configurations
Diversity Mode Number of Sectors
(AU-IDUs)
Number of ODUs Number of Power
Feeders
Second Order Diversity 3 6 -
48 1
6122
Fourth Order Diversity 3 12 2
4163
6245