Digital Expansion Unit Description - ADC Digivance Installation And Operation Manual

ADCP-75-130 • Issue 3C • August 2006

2.3 Digital Expansion Unit Description

The DEU, shown in Figure 6, serves as a service expansion unit and line extender for the
Digivance ICS. The DEU provides the following basic functions:
•
Optical interface to the DHU and up to six DRU's or DEU's
•
Conversion of the forward path digitized optical signal to an electrical bit stream
•
Splitting of the electrical bit stream into six separate bit streams
•
Conversion of the six forward path electrical bit streams into six digital optical signals
•
Conversion of up to six reverse path digital optical signals into six serial bit streams
•
Combining of the six reverse path serial bit streams into a single digital composite signal
•
Conversion of the single digital composite signal to a digital optical signal
•
DC power for powering the DRU's
•
Alarm transport via the optical fibers
3.5 INCHES
(89 mm)
11.4 INCHES
15.3 INCHES
(389 mm)
2.3.1 Primary Components
The DEU consists of two electronic circuit board assemblies and a power supply that are
mounted within a powder-coated sheet metal enclosure. The metal enclosure provides a
mounting point for the electronic assemblies and serves as a heat sink. Except for the fan units
and optical transceivers, the DEU components are not field replaceable. The DEU is designed
for use within a non-condensing indoor environment such as inside a wiring closet or cabinet.
All controls, connectors, and indicators are mounted on the DEU front panel for convenient
access. Cable management functions for the power and fiber optic cables are provided by a
cable management tray that extends outward from the DEU front panel.
2.3.2 Mounting
The DEU may be used in both rack-mount and wall-mount applications. For rack mount
applications, a pair of reversible mounting brackets is provided that allows the DEU to be
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© 2006, ADC Telecommunications, Inc.
(290 mm)
Figure 6. Digital Expansion Unit
17.2 INCHES
(437 mm)
FRONT PANEL
MOUNTING
BRACKET
(BOTH SIDES)
17270-A
CABLE MANAGEMENT
TRAY