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III –
12
3. CONTROL ELECTRONICS
3.1
Configuration
The configuration of the facsimile equipment is shown below.
Main PCB
Control
panel
PCB
Relay
PCB
*
1
ASIC
MODEM
Laser unit
Toner sensor PCB *
2
Fixing
Unit
Heater thermister
Heater (FU lamp)
Fan 2
Main motor
Solenoid
AC line
Low-voltage
power supply
PCB
Document
sensor PCB
*
4
CCD unit
LED array
Scanner
motor
Speaker
NCU PCB
Line
External TEL
Handset
36-pin
P15
P1
8-pin
P2
40-pin
P3
30-pin
5-pin
P5
P13
26-pin
P18
2-pin
4-pin
P9
P8
2-pin
P7
5-pin
P4
P10
6-pin
P16
2-pin
P6
(Note)
P11
2-pin
5-pin
5-pin
4-pin
12-pin
High-voltage
power supply PCB
*
3
Fan 1
Eraser lamp board
3-pin
4-pin
LASER PRINTING
UNIT
SCANNER
UNIT
P1
P3
P2
P4
*
1
On the relay PCB are these sensors:
• Cover sensor
• Sheet feeder cover sensor
• Registration sensor
*
2
On the toner sensor PCB are these sensors:
• Toner sensor
• Toner thermister
*
3
On the high-voltage power supply PCB is the paper
ejection sensor.
*
4
On the document sensor PCB are these sensors:
• Document front sensor
• Document rear sensor
*
5
On the hook switch PCB is the hook switch sensor.
Configuration
Polygon motor
Laser diode
*
5
Hook switch
PCB
Extended RAM
connector
(Note)
12-pin: U.S.A. versions
18-pin: European and Asian
versions
Centronics parallel
interface (MFC4450/
4550/4550plus/
6550MC/7550MC/
7650MC/9000/9500)
Modular
connector for
PC interface
(FAX3550/3650/
8000P/8200P)
Extended I/O
connector
(MFC6550MC/
7550MC/7650MC/
9000/9500)
11-pin
Summary of Contents for MFC 4550
Page 5: ...CHAPTER I GENERAL DESCRIPTION ...
Page 14: ...CHAPTER II INSTALLATION ...
Page 15: ...CONTENTS 1 INSTALLING THE UPDATE DATA TO THE FACSIMILE EQUIPMENT II 1 ...
Page 18: ...CHAPTER III THEORY OF OPERATION ...
Page 49: ...CHAPTER IV DISASSEMBLY REASSEMBLY AND LUBRICATION ...
Page 81: ...CHAPTER V MAINTENANCE MODE ...
Page 89: ...V 7 Scanning Compensation Data List 200 dpi ...
Page 133: ...CHAPTER VI ERROR INDICATION AND TROUBLESHOOTING ...
Page 163: ...MAIN 8 8 FAX3550 3650 8000P 8200P MFC4550 6550MC 7550MC MFC9000 9500 A ...
Page 185: ...D CONTROL PANEL 1 2 ...
Page 187: ...E POWER SUPPLY 120 V Low voltage power supply ...
Page 188: ...E POWER SUPPLY 200 240 V Low voltage power supply European versions ...
Page 189: ...E POWER SUPPLY 200 240 V Low voltage power supply Asian versions ...
Page 190: ...E POWER SUPPLY High voltage power supply ...
Page 191: ...Sept 98 5X52012 Printed in Japan ...