Bosch F.01U.393.727, Installation Manual

16

en | Installation

Loudspeaker line isolator system

2021.07.28 | V1.00 |

Installation manual

Bosch Security Systems B.V.

i

Notice!

If any short circuit is present on the speaker cable, LDB will immediately detect and isolate
the shorted connector and SHORT indication will appear on LDB front panel. If the speaker
cable connects to ground causing earth leakage, LDB will detect the earth leakage and EARTH
fault indication will appear on LDB front panel. See 

PRA-LID (LDB) Indicators, buttons and

connections, page 9.

5.

If system includes multiple loops (multiple LDBs), there is a number of ways you can
interconnect Loudspeaker line isolator to the Public Address / Voice Alarm system.

6.

If you are planning to proceed with installation of FIM modules on the loop, leave the

SECONDARY

 output of LDB disconnected.

7.

When loop is closed, and all FIMs on the loop are working properly, connect the incoming
loop cable to 

SECONDARY

 output of LDB. Loop is now fully secured.

Multiple LDBs can share common fault contact or individual fault control contacts of the main
system. Fault contact sharing allows you to reduce number of control inputs needed for fault
reports. Detailed information about the location and type of fault is always available on LDBs
front panels, as well as via Sniffer PC application.
Multiple LDBs can also share common power amplifier or have individual power amplifiers
from the main system. Amplifier sharing allows you to create multiple loops within one zone,
each with individual surveillance.

Refer to

–

PRA-LID (LDB) Indicators, buttons and connections, page 9

4.6

Installing PRA-LIM (FIM) on a loudspeaker line

Before you start connecting FIMs on the loop, make sure that LDB is connected to the rail and
powered. See 

Installing order PRA-LID (LDB), page 15.

1.

For most efficient installation make sure that LDB is in 

SERVICE

MODE

 (blue 

MODE

indicator blinking fast).
–

To put LDB into 

SERVICE

MODE

 press SERVICE button for 10 seconds or use Sniffer

PC application.

2.

During 

SERVICE MODE

 LDB will show 

OPEN

 fault indication as long as the loop is not

completely closed.
–

This is the correct indication, since the loop should be closed only at the final stage
of installation, to make sure that the entire course of the loop is complete.

i

Notice!

When the loudspeaker line isolator system is in SERVICE MODE, audio signal from power
amplifier is not transmitted to the loop.

3.

Double check if the loudspeaker line cable is connected to the 

PRIMARY

 loop output of

LDB and the 

SECONDARY

 loop output of LDB is not connected.

4.

LDB should indicate only 

OPEN

 fault. If 

SHORT

 fault is detected, fix it before FIM

installation.

5.

Check if 

EOL

 switch (

6

) on the FIM is in 

OFF

 position.

i

Notice!

EOL switch (6) should be in ON position only with EOL resistor connected to the termination
of T‑Branch line. Short circuits on T‑Branch are detected and isolated regardless the EOL
monitoring switch.