Fusercontrol - Epson ActionLaser 1300 EPL-3000 Service Manual

Operating Principks
2.1.2.3
surface temperature of the upper fusing roller is detected by thermistor THl and the
The
corresponding a&log voltage is appii~ to IC20i pin 62.
Heater lamp HI is turned on or off to provide fusing temperature control
on/off signal output from IC201 pin%.
If HI is not turned off when THl detects an abnormally high fusing
automatically turned off as follows.
When the surface temperature of the upper fusing roller detected by THl exceeds 200 W (392 "F),
the voltage applied to 1(202 pin 42 becomes higher than the reference voltage at IC202 pin 41. Then
the outout from comparator goes from HIGH to LOW. When this occurs, the output from the
Heater Lamp ON/OFF Signal
C144 MAIN
Section
The diagram below shows fluctuations in the temperature after the power supply has been turned
on.
168
135
100
c )
0
(
2-12
Board
H <-- L L <-- H
NAND
Circuit
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Figure 2-18. Fuser Control Circuit
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Figure 2-19. Tempwature Control
Thermistor (TH1) analog voltage
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t
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1
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by the heater lamp
temperature, H1 is
(CPU)
46
t
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Mode
By
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Rev. A