Line Input - Bosch PRAESENSA Installation Manual

PRAESENSA
12.5.5

Line input

On the left side of the call station is a 3.5 mm stereo socket. This is an input for a background
music source, such as a dedicated audio player, smartphone or PC. The stereo signal is
converted to mono for further distribution in the system. This input needs to be configured in
the system for this function, to link it to a background music channel that is available for
playback in one or more system zones. This input is not supervised, unplugging the cable to
the audio player will not be reported as a fault.
Notice!
When music is played from a PC that is connected to a grounded mains supply, there is a risk
of hum being inserted into the music input of the call station. This is caused by unequal
ground potentials of the different mains supplies. Use a cable with integrated transformers
for ground loop isolation to prevent such hum. See picture below of an example ground loop
isolator cable.
Notice!
For compliance to DNV GL type approval, the line input must not be used. By connecting a
cable to this input the radiated emission of the device would exceed the limit for the maritime
radio band.
Bosch Security Systems B.V.
LCD call station | PRA-CSLD, PRA-CSLW | en 137
Installation manual 2019.11 | V1.00 |