2
9) Rated output power:
350W
10) Operating environment:
Temperature 0 ~ + 40
℃
, relative humidity 95%
11) Insulation strength:
a) AC input to the chassis greater than 50M (DC500 V)
b) Constant voltage
output to the chassis greater than
50M
(DC500 V)
12) Electrical strength:
AC input to the chassis leakage less than 10mA (AC 1
,250V)
1.4 Logistic schematic diagram
Fig. 1.2 Logic schematic diagram
External line 2
External line 1
Microphone
Keyboard and
indicator
Background
music/Emergency
broadcast
MCU
Fault message
feedback
Power
amplification
Output
485 communication port
Volume
adjustment
Sound
source
switching