Bosch LBB 1938 - Low Impedance Loudspeaker Connection; Mains Connection

Bosch Security Systems | 2003-09 | 3922 988 92983en
Plena Booster Amplifier | Installation and Operating Manual | en | 17
LBB1938 only:
Ensure that the fuse for loudspeaker voltage selection is properly set (see chapter 2). The Priority Only and No
Priority outputs are controlled by a priority relay. The Priority Only output only provides priority announcements,
while the No Priority output just provides the program signal and switches OFF at priority calls. You can also use
the Priority Only output for 3-wire remote volume control override. In this case, ensure that the selected voltage for
the Priority Only output is the same as for the direct output used.
4.5.2Low impedance loudspeakers
Connect low impedance loudspeakers to the 8 Ohm/0 terminals. This output can deliver the rated output power
into an 8 Ohm load. Connect multiple loudspeakers in a series/parallel-arrangement to make the combined
impedance 8 Ohm or higher. Check the loudspeaker polarity for in-phase connection.
4.6 Mains connection
Figure 4.11 Figure 4.12
Use the supplied mains cord to connect the system to the mains supply.
Note (LBB 1930 and LBB 1935 only)
If necessary set the mains voltage switch 230/240 V (11) to the required voltage using a sharp object,
e.g. a small screwdriver.
2
3
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-
2
4
0
V
-
70
V
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LBB1930
LBB1935
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7
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0
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1
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V
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100V
0
LBB1938
External settings and connections