Technical information

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COPYRIGHT © 2001 CANON INC. 2000 2000 2000 2000 CANON CLC5000 REV.0 JAN. 2001
CHAPTER 2 NEW FUNCTIONS
6.4 Controlling the Fixing Roller Temperature
The fixing upper roller and the fixing lower roller are each heated by a fixing heater (H1:
800 W; H2: 600 W). The surface temperature of the upper roller is monitored by the upper
main thermistor (TH1), while that of the lower roller is monitored by the lower main ther-
mistor (TH3).
The CPU on the DC controller PCB uses the readings of these thermistors to control the
fixing heaters by means of the upper fixing heater drive signal (UHON) and the lower fixing
heater drive signal (LHON) so that the surface temperature of the upper and lower rollers
remain at a specific level.
• Upper Fixing Roller/Lower Fixing Roller (common)
During copying: controlled to 175ºC (One-sided), controlled to 170ºC (Auto two-
sided mode)
During STBY: controlled to 182ºC
During pre-heat: controlled to 182ºC
The upper sub thermistor (TH2) and the lower sub thermistor (TH4) are attached to the
ends of the rollers for detection of errors.
REF.
Shifting down the fixing assembly lever, as when drawing out the fixing as-
sembly, will cut off the power to the fixing heater using the fixing lever
switch (SW5).