Bosch PLE-4MA240-CN - Page 8

8 en | Introduction PLENA Mixer amplifier, 4-zone, 240W
2019-03 | V1.1 | Operation manual Bosch Security Systems B.V.
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.
EMERGENCY
-
+
VOX
-
+
PTT DETECT
24V
PH-24V
MIC/LINE1
EMG-VOX
GAIN
MIC1-TR
PH SWITCH
-
+
MIC2
SOURCE-SELECT
AUX 1
-
+
MIC3
GAIN
DUCKING
CLASS D
LIMITER
CLASS D CTRL
B+
-
+
CHIME
LINE OUT
ZONE 1~4
MONITOR
VU-METER
MUTE
AUX 2
RELAY
I2C
100V
MIC1/LINE
MIC2
MIC3
AUX
BASS
TREBLE
MASTER VR
Micro
controller
TEL-EMG/MIX
SELECT
LINE-OUT
MUTE
ZONE1~4
AUX1~3
PRIO
CHIME ON/OFF
B+ (50VDC/6A)
+5VDC/1A
+28VDC/1A
SMPS
B+ ON/OFF
+24VDC/500mA
+28VDC
LDO
+3V3/250mA
+5VDC
LDO
+9VDC/100mA
230VAC
EMC
24VDC/100mA
SUPPLY
24V-PRIO
+24VDC
+24VDC
ZONE1~4 BUTTON
SOURCE BUTTON
FILTER
MIC/LINE
SWITCH
DUCKING
GAIN
ZONE CONTROL
TONE
CONTROL
BASS
TREBLE
MASTER
GAIN
SPI
I2C
EEPROM
-
+
ADC
ATTN
AUX 3
24V
PH-24V
PH SWITCH
24V
PH-24V
PH SWITCH
Figure3.1: Schematic overview of PLE-4MA240-CN