Bosch PLENA Series Operation Manual page 8

8 en | Introduction
Input 1 can take priority over all other microphone and music inputs: Input 1 priority can be
activated by contact closure on the PTT (push to talk). A 2-tone chime can be configured to
precede an announcement.
The volume of each microphone input can be individually adjusted to obtain the required mix;
the mixed output is controlled via the master volume control and separate high/low tone
controls.
Separate music inputs are available with their own input selector and volume control. The user
can choose a music source like a CD/DVD player or radio (like the PLE-SDT), and set the level
of music. A front panel music input makes it easier to connect a hand-held device as music
source.
A telephone / 100V emergency input is provided for easy integration with a telephone paging
system or another Public Address system. It has its own preset volume control and overrides
all other inputs, including input 1.
The unit also provides a 24V DC output to override remote loudspeaker volume control
whenever there is a telephone or emergency input signal.
The unit has a line output to add amplifiers for larger systems with more output power.
Users can create custom labels for inputs, music sources, and output zones. These labels can
be attached to the special holders at the front of the mixer amplifier. Colored pins can also be
inserted at various positions around the volume and tone controls to indicate favorite settings
for a particular application.
An LED VU meter monitors the master output. A headphone socket, below the VU meter,
provides the mixer output. For total reliability and ease of use, a limiter is integrated into the
output stage to restrict output if the user applies too much signal.
For a schematic overview of the PLENA Mixer amplifier, see figure 3.1.
ZONE 1~4
24VDC/100mA
Figure 3.1: Schematic overview of PLE-4MA240-CN
2019-03 | V1.1 |
-
+
VOX
100V
- +
-
+
GAIN
MIC1-TR
PTT DETECT
24V
PH SWITCH
PH-24V
-
+
MIC/LINE
SWITCH
PH-24V
24V
PH SWITCH
-
+
24V
PH-24V
PH SWITCH
-
+
AUX 1
AUX 2
SOURCE-SELECT
+24VDC
ZONE CONTROL
CLASS D
RELAY
SUPPLY +24VDC
B+
24V-PRIO
B+ ON/OFF
EMC
230VAC SMPS
MUTE
LINE-OUT
MUTE
EMG-VOX
ATTN
GAIN
CHIME
CHIME ON/OFF
GAIN
DUCKING
I2C
CLASS D CTRL
LIMITER
FILTER
+3V3/250mA
LDO
+5VDC
B+ (50VDC/6A)
+9VDC/100mA
+5VDC/1A
LDO
+28VDC/1A
+28VDC +24VDC/500mA
Operation manual
PLENA Mixer amplifier, 4-zone, 240W
Micro
controller
I2C
EEPROM
DUCKING
ADC
TONE
CONTROL
MASTER
TREBLE BASS
GAIN
SPI
TEL-EMG/MIX
SELECT
Bosch Security Systems B.V.
MIC1/LINE
MIC2
MIC3
AUX
BASS
TREBLE
MASTER VR
ZONE1~4
AUX1~3
PRIO
ZONE1~4 BUTTON
SOURCE BUTTON
AUX 3
MONITOR
VU-METER