COPYRIGHT
©
1998 CANON INC. CANON NP7161/NP7160 REV.0 AUG. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)

6–5

CHAPTER 6 FIXING SYSTEM
C. Error Detection Circuit

1. Outline

The copier’s error detection circuit is constructed as shown in Figure 6-104, and monitors the

following items for an error:

Surface temperature of the upper fixing roller

Activation of the fixing heater (H1)

Figure 6-104

DC controller PCB
Power supply PCB
HVT
Fixing assembly
TH2
TH2
TH1
TH1
HEAT_ERR
AC_24V_ON
TH1_DT
J108-3
-2
-4
-1
J109-2
-1
J106
-19
J106
-24
J212
-6
J212
-1
TSWH1
+5V
+5V
+5V +5V
Buffer
Buffer
+
-
-
+
Gate
array
timer
Error
detection
circuit
IC119
CPU
IC113
Heater ON
detection
Converter
AC
driver
RL1
J201
-2
-1
J210
-1
-2
LF
DS1 RL
CB1
CB2
AC power line
DC signal line
+24V