AM-300 (serv.man5). Chapter 5 (Circuit Description). - Sharp Copying Equipment Service Manual (repair manual). Page 13

Read Sharp AM-300 (serv.man5) Service Manual online

AM-300DE
5 – 13
3. Printer mechanism control block
3.1. Unit control
3.1.1 High voltage unit control
The high voltage unit outputs the following voltages:
• Main charger voltage (DC-950V + AC760V peak to peak)
• Transfer charger voltage (DC+3600V + AC760V peak to peak)
• Developing bias voltage (DC-180V)
The following signals are outputted from the CPU and Logic to con-
trol the above voltages.
• MCON
This signal is to turn on/off the main charger.
When this signal is outputted.
As a result, the main charger voltage is outputted to the secondary
side of the transformer (B51).
• TCON
This signal is to turn on/off the transfer charger and the developing
bias voltage.
• PWMSIN
This signal is to control the main charger voltage and the transfer
charger voltage. The PWM pulse of about 300Hz is outputted.
This pulse waveform adds the AC component to the main charger
voltage and the transfer charger voltage.
By changing the pulse duty of this signal, the main charger voltage
and the transfer charger voltage are controlled.
3.1.2 Electrical connection
Fig. 8
CONTROL PWB
16bit CPU
IC21
57
56
TCON
MCON
PWMSIN
Constant
voltage
control
circuit
PWM
control
circuit
Logic
circuit
Oscillation
circuit
B51
Transformer
High Voltage PWB Unit
Constant
voltage
control
circuit
Oscillation
circuit
Feedback circuit
Feedback circuit
B1
Transformer
HV(+)
Rectifier
circuit
HV(-)
Rectifier
circuit
HV(-)
Rectifier
circuit
Constant
voltage(+)
circuit
Constant
voltage(-)
circuit
Short
circuit
Short
protection
circuit
SV
DV
MC
TC
110M
Ω
250MΩ
FU-EARTH
LASER MFP
Transfer Roller
Supply Roller
Developing Roller
Charger Roller
Heat Roller
Pressure Roller
Doctor
OPC DRUM
Separation electrode
Page of 30
Display

Click on the first or last page to see other AM-300 (serv.man5) service manuals if exist.

Random: