e-STUDIO2006/2306/2506/2007/2307/2507/2303A/2303AM/2803AM/2309A/2809A
© 2013-2017 TOSHIBA TEC CORPORATION All rights reserved
OUTLINE OF THE MACHINE
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2. Temperature detection configuration
Thermistor is a device whose resistance decreases as it detects a higher temperature. Thus its input
voltage to A/D converter changes and then SoC judges whether this change is normal or abnormal.
If one of the fuser roller thermistors is broken, the control circuit judges that the fuser roller
temperature is extremely low and keeps turning the heater lamp ON. As a result, the fuser roller
temperature rises, and possibly activates the thermostat which is a safety protection device. To
prevent this in advance, SoC works to detect whether each thermistor is broken or not.
Also, the thermistors constantly check the temperature of heater lamp to prevent it from excessive
heating by MAIN circuit abnormality or thermistor abnormality. The thermistors automatically turn
OFF the power when the temperature of heater lamp exceeds the specified temperature.
3. Abnormality detection by the thermistors
The following table shows the conditions judging the fuser roller temperature abnormality and
detecting timing.
Operating state
Error
code
Error
counter
Evaluation temperature
Check
timing
Center
thermistor
Side
thermistor
Edge
thermistor
Power ON
Ready
When power
ON
C449
9 confirmed
240ºC
-
-
When
power ON
-
240ºC
-
-
-
240ºC
When 40ºC
detected
C449
19 confirmed
240ºC
-
-
Constantly
detected
-
240ºC
-
-
-
240ºC
C411
1
unconfirmed
40ºC
-
-
C40
-
40ºC
-
S40
C412
2 confirmed
40ºC
-
-
C40
-
40ºC
-
S40
When 100ºC
detected
C449
21 confirmed
240ºC
-
-
Constantly
detected
-
240ºC
-
-
-
240ºC
C413
3 confirmed
100ºC
-
-
C100
-
100ºC
S100
Ready
temperature
C449
22 confirmed
240ºC
-
-
Constantly
detected
-
240ºC
-
-
-
240ºC
C452
62 confirmed
Ready
temperature Center 70ºC
-
C-Ready
S-Ready
Center 70ºC
Ready
temperature
-
C414
4 confirmed
Ready
temperature
-
-
-
Ready
temperature
-