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AR-651/810 FUSER UNIT 14 - 8
14. 4. 5. Temperature detecting section
To keep the fuser roller at a certain temperature, the center thermistor and side thermistor (rear) detect the
temperature of the fuser roller and control ON/OFF of the IH coil. Outputs from the thermistors are used to
detect abnormalities of the fuser roller temperature.
(1) Relation between the thermistor output voltage and surface temperature of the fuser roller:
Approx. 4.0V when the temperature is 200°C
Approx. 3.8V when the temperature is 183°C, and approx. 3.7V when the temperature is 177°C.
(2) Temperature control for the surface of the fuser roller:
(3) Temperature control for both ends of the fuser roller
During the multiple copying, the temperature of both ends of the fuser roller (where a paper does not
pass on) generally becomes higher than that of the other areas (where a paper does pass on). The side
thermistor (front) detects the temperature of the ends, in this case, it controls the center IH coil and
side IH coil to unify the fuser roller temperature.
(4) Error detection during warming up (1)
If the output voltage of either the center thermistor or side thermistor (rear) does not go over approx.
0.5V(40°C) even in a certain period of time after the heater has turned ON, the “Call for service” [C41]
is displayed.
C
ON
ON
ON ON ON ON
ON ON
ON
ON
OFF
OFF
0
0
0
65
81
81 65
81
0
65
0
AR-810
Temperature
Fusing control
200°C and above
IH coil turned OFF
183~200°C
IH coil turned ON
Normal copy speed
177~183°C
Copying continued but the copy speed lowered (AR-810 only)
Below 177°C
Copying interrupted and back to the ready
Temperature
of fuser roller
Herter
177
183
200
Copy speed
(A4/LT)
Warming-up
Ready (200°C) During copying
Ready
During
copying
During
waiting
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