Bosch 3.5 User Manual

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Bosch Security Systems | 2011-02
Praesideo 3.5 | Installation and User Instructions | 4 | Amplifiers
en | 137
8.3.5 Connecting the amplifier channels
8.3.5.1 Introduction
An amplifier channel (see figure 8.4) is a group of 
outgoing signals that have been processed by the same 
amplifier unit of the power amplifier. The number of 
amplifier channels depends on the type of power 
amplifier (see table 8.3).
table 8.3: Number of amplifier channels
Type
Amplifier channels
PRS-1P500
1
PRS-2P250
2
PRS-4P125
4
LBB4428/00
8
figure 8.4: Amplifier channel connector
table 8.4: Amplifier channel connector details
Pin
Description
1, 2, 3
Control outputs contacts. See 
4, 8
Spare amplifier. See section 8.3.5.5.
5, 9
Loudspeaker line. See section 
6, 7
Fixed 50 V line. See section 8.3.5.3.
C
Control Out
Spare In
Lsp Out
NO NC
0V
50V
1
9
Caution
To prevent the hazard of electric shocks, switch 
off the power amplifiers and disconnect the 
back up power supplies from the power 
amplifiers before connecting loudspeaker lines 
and spare amplifier connections. 
Caution
After connecting wires to the amplifier channel 
connectors, install the plastic safety bracket. 
The plastic safety bracket makes sure that the 
amplifier channel connectors cannot be 
touched.