Dcn Design; Introduction; Concepts; Limitations - Bosch DCN Next Generation Installation And User Instructions Manual

DCN NG | Installation and User Instructions | Section 5 | System Installation
26

DCN Design

26. 1

Introduction

This chapter provides information about installing the
DCN.

26.2 Concepts

26.2.1 Introduction
Before the limitations for the DCN are described (see
section 26.3) first a number of concepts, necessary to
understand the limitations, are explained.
26.2.2 Trunk and tap-offs sockets
In the DCN, two types of sockets are available: trunk
sockets and tap-off sockets. Trunk sockets are intended
for looping the DCN trunk through (except for the
DCN trunk sockets on the CCU), whereas tap-off
sockets are used to create additional branches. A tap-off
socket always regenerates the digital DCN signal.
26.2.3 Unit cables and extension cables
All units that can be put in the DCN have an attached
cable. This unit cable is 2 m long. If necessary, these
unit cables can be extended with extension cables
(LBB4116/xx).
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26.3 Limitations

Observe the following limitations when designing the
DCN:
Limitation 1: Control capacity
The maximum number of active units in the DCN that
can be controlled by the CCU is 245 (see section 26.4).
Limitation 2: Power capacity
The maximum power that can be supplied by a single
CCU (LBB4100/00) socket is 65 W. The maximum
power that can be supplied by a single extension power
supply (LBB4106/00) socket is 85 W (see section 26.5).
Limitation 3: Tap-off connections
The number of serial tap-off connections from the CCU
(LBB4100/00) to the last tap-off in a branch must not
exceed 4. Any unit connected thereafter will not
function correctly (see section 26.6).
Limitation 4: Loop-through connections
The maximum number of loop-through connections in
succession is 50. After 50 loop-throughs, the signal must
be regenerated (see section 26.7).
Limitation 5: Cable lengths
• The total cable length between the CCU
(LBB4100/00) and the last unit in any branch of the
DCN must not exceed 250 m if regenerative tap-offs
are used.
• The total cable length of the cable from the CCU
(LBB4100/00) to the first regenerative tap-off must
not exceed 100 m.
• The total length of the cable between regenerative
tap-offs must not exceed 100 m.
Note
The total cable length includes the 2 m long unit
cables.
See section 26.8 for information about cable length
limitations.
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