Specifications

Bosch Security Systems | 2007-08 | 9922 141 50672en
Plena Loop Amplifier | Installation and User Instructions | Configuration en | 27
5 Configuration
5.1 Master and slaves
Set the Master in/Slave out switches on the rear of all
loop amplifiers (refer to figure 5.1) in the induction loop
system in the correct position.
•The Master/Slave switch of the master loop amplifier
must be in the Master position.
•The Master/Slave switch of all slave loop amplifiers
must be in the Slave position.
5.2 Electric current
5.2.1 Master induction loops
Do as follows:
1 Connect a pink noise source to audio input 2 on the
rear of the master loop amplifier.
2 Connect the master loop amplifier to the mains
power supply with a power cable.
3Set the AGC/Limiter switch on the rear of the master
loop amplifier in the Limiter position.
4 Switch on the pink noise source.
5 Set the signal strength of the output signal of the pink
noise source to 0 dBV.
6 Switch on the master loop amplifier with the power
switch on the front.
7 Increase the volume of audio input 2 of the master
loop amplifier with its input volume control until the
Limiter LED on the front of the master loop amplifier
comes on.
8 Increase the electric current through the master
induction loops with the Master volume control on
the front of the master loop amplifier until the
magnetic field strength in each master induction
loop is 100 mA/m.
9 Switch off the master loop amplifier with the power
switch on the front.
10 When the induction loop system contains slave loop
amplifiers, configure the electric current through the
slave induction loops (refer to section 5.2.2).
figure 5.1: Master/Slave switch
Note
Slave loop amplifier can only send the signal
that they receive from the master loop amplifier
to their induction loops. The audio inputs and
the priority input of the slave loop amplifiers are
disabled.
VU LED
PRE Amp. POST Amp.
Master Slave
Master In
Slave Out
0º 90º
Note
Instead of a pink noise source, you can use a
sine wave of 1 kHz. Then, the magnetic field
strength must be 70 mA/m in each master
induction loop.