1AF
2-3-4
(1) Fixing unit abnormally high temperature/shorted thermistor detection circuit
CN11-25
CN11-26
H REM
CPCB
S G
S G
–
+
S
CN4-6
R96
IC20
7
6
5
TR3
65
3
R98
S
S G
S
FTH
CPU
(IC11)
I/O
(IC6)
39
H
Figure 2-3-3
Fixing unit abnormally high temperature/shorted thermistor
detection circuit
The fixing unit abnormally high temperature/shorted thermistor detection circuit forces the
fixing heater control signal H REM off if the fixing temperature reaches an abnormally high
level. This hardware safety function backs up the software-controlled shorted fixing unit
thermistor/abnormally high temperature detection feature (self-diagnostic code C64).
As the fixing temperature rises, the resistance of the fixing unit thermistor (FTH) decreases.
This increases the voltage at pin 6 of comparator IC20. When the voltage exceeds the
abnormality detection level set by resistors R96 and R98 at pin 5 of comparator IC20, the
output at pin 7 goes low, turning transistor TR3 off; this shuts off the fixing heater control
signal H REM output from pin 3 of the CPU (IC11), forcing off the fixing heater (H) controlled
via the composite PCB (CPCB).
Содержание DC-1560
Страница 1: ...DC 1560 2050 KME S M SERVICE MANUAL Published in Oct 99 841AF110 DC 1560 2050 DC 1560 2050...
Страница 3: ...SERVICE MANUAL DC 1560 2050...
Страница 12: ...1 1 5 1AF CONTENTS 1 1 Specifications 1 1 1 Specifications DC 2050 1 1 1 1 1 2 Specifications DC 1560 1 1 3...
Страница 13: ...1 1 7 1AF CONTENTS 1 2 Handling Precautions 1 2 1 Drum 1 2 1 1 2 2 Developer and toner 1 2 1...
Страница 15: ...1 1 11 1AF CONTENTS 2 1 Electrical Parts Layout 2 1 1 Electrical parts layout 2 1 1...
Страница 23: ...1 1 27 1AF CONTENTS 3 5 Self Diagnostics 3 5 1 Self diagnostic function 3 5 1 1 Self diagnostic display 3 5 1...
Страница 27: ...DC 1560 2050 KME S M I Theory and Construction Section THEORY AND CONSTRUCTION SECTION I...
Страница 28: ...1 1 5 1AF CONTENTS 1 1 Specifications 1 1 1 Specifications DC 2050 1 1 1 1 1 2 Specifications DC 1560 1 1 3...
Страница 33: ...1 1 7 1AF CONTENTS 1 2 Handling Precautions 1 2 1 Drum 1 2 1 1 2 2 Developer and toner 1 2 1...
Страница 78: ...DC 1560 2050 KME S M ELECTRICAL SECTION II II Electrical Section...
Страница 79: ...1 1 11 1AF CONTENTS 2 1 Electrical Parts Layout 2 1 1 Electrical parts layout 2 1 1...
Страница 98: ...DC 1560 2050 KME S M III Set Up and Adjustment Section III SET UP AND ADJUSTMENT SECTION...
Страница 114: ...3 1 15 1AF Make test copies 1 Place paper in the paper drawer and make test copies Completion of machine installation...
Страница 169: ...1AF 3 3 13 End Yes No Press the stop clear key Exit simulation mode Adjust for another mode...
Страница 201: ...1AF 3 3 45 End Yes Press the stop clear key Exit simulation mode No Adjust for another mode...
Страница 229: ...1 1 27 1AF CONTENTS 3 5 Self Diagnostics 3 5 1 Self diagnostic function 3 5 1 1 Self diagnostic display 3 5 1...