Bosch PVA-4CR12, Руководство по эксплуатации

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Notice!
The total impedance connected at the output on the amplifier (loudspeakers and cabling)
must be within the specified impedance range in terms of the test frequency (see the table
entitled “Impedance measuring specification”).
Notice!
To detect a line interruption to a single speaker, or the failure of a single speaker, the
following instructions must be observed: Do not connect more than five speakers to one
speaker line. All speakers on the speaker line must have the same impedance.
EOL slave module
End-of-line (EOL) technology enables the loudspeaker lines to be monitored for short-circuit
and interruptions. The EOL modules can be used for permanent supervision on not active and
active speaker lines, e.g. for speaker lines with permanent background music or if passive
volume controls are used.
Method of operation
An EOL slave module PVA-1WEOL is installed at the end of the speaker line. The speaker line
is used for both the power supply of the module (via the non-audible pilot tone) and for bi-
directional communication between the EOL master in the output stage and the EOL slave
module (using very low-frequency signals). If a communication error occurs – for example, if
the EOL master does not receive a response from the slave – then an error message is
generated. The unique addressing of the slave modules means that multiple slave modules can
be connected to one speaker line.
For communication between the master and the slave modules, the EOL slave modules must
be connected to ground. The shielding on the speaker cable, a free wire in the speaker cable,
or any other available ground point – such as the safety ground of the power supply system –
can be used for this purpose. The resistance R
G
between an output line of the amplifier and
ground must be at least 1.5 MΩ. The capacity C
G
between an output line of the device and the
ground must not be greater than 400 nF.
+
-
-
Filter DC/DC
Send/
Receive
Control
Address
S
Speaker -
Shield / Wire / Ground
R
G
C
G
Figure 8.1: Circuit diagram (R
G
and C
G
are caused by the loudspeaker installation, e.g. wire type, length)
EOL monitoring function setup
Connect the EOL slave modules to the end of the speaker line. Set the desired address at the
DIP switches
➊
. For details please refer to the installation note of the PVA-1WEOL.
8.1.2
38 en | Operation PAVIRO Controller
08-May-2017 | 04 | F01U306900 Operation manual