Xerox Phaser 3300 Servce Manual page 76

Theory of Operation
2-34
Fusing
The temperature change of the heat roller's surface varies with the resistance
value through the thermistor. The resistance value determines how much
voltage will be converted into heat to raise the temperature of the fuser. If the
value measured by the thermistor is out of controlling range, one of the errors
below may occur:
Error
Open Heat Error
Over Heat Error
Low Heat Error
Open Heat Error
This error occurs when a specified temperature is not reached during the
warm up process. When this happens, the engine stops all functions and
processes. The engine then informs the error status to the main system. An
error message is then displayed on the LCD which informs the user.
Recovery is performed automatically. Maximum heat is supplied to the fuser
and a second reading is taken. When the specified temperature is reached,
the printer resumes operation as normal.
Low Heat Error
This error occurs when the temperature is lower than the specified
temperature during stand-by, printing or warm-up mode. When this happens,
the engine stops all functions and processes. The engine then reports the
error status to the main system. An error message is then displayed on the
LCD which informs the user.
Recovery is performed automatically. Maximum heat is supplied to the fuser
and a second reading is taken. When the specified temperature is reached,
the printer resumes operation as normal.
Over Heat Error
This error occurs whenever the printer temperature is higher than specified.
When this happens, the engine stops all functions and processes. The engine
then informs the error status to the main system. An error message is then
displayed on the LCD or LED which informs the user.
Recovery is performed automatically. The heat supply is cut off to the fuser
and a second reading is taken. When the temperature is a degree below the
specified temperature, printer resumes operation as normal.
Temperature Control Concept
90 °C below for 45 sec at Warm up
230 °C over for 10 sec or 240 over for 5 sec
Standby: 130 °C below for 10 sec
Printing: 35 °C below for 7 sec at consecutive 2 page printing.
Phaser 3300MFP Service Manual