Controlling The Temperature By A Fluorescent Lamp Heater; Controlling Pre-Heat Voltage - Canon ImageRunner 600 Service Manual

CHAPTER 3 ORIGINAL EXPOSURE SYSTEM
B.

Controlling the Temperature by a Fluorescent Lamp Heater

The fluorescent lamp controls the area around the fluorescent lamp to 70°C to ensure a stable
light intensity.
Main power
switch ON
Fluorescent heater
(H5)
Scanning lamp
(FL1)
C.

Controlling Pre-Heat Voltage

A pre-heat voltage is applied to the fluorescnet lamp even when the lamp remains off so as to
ensure an optimum intensity in the shortest time possible.
Fluorescent heater
(H5)
Scanning lamp
pre-heat voltage
Scanning lamp
(FL1)
The scanning lamp is assumed to
have reached its optimum intensity
when the temperature of the area
around it reaches 70˚C. Then, the
pre-heat voltage is increased to
prepare for activation.
Figure 3-303 Pre-Heat Voltage Application Sequence
Standby
pre-heating
Pre-heating
before
activation
Pre-heating
3.9 V to 3.8 V (optimum
during
level is applied to suit
activation
the measurement of the
light intensity sensor)
3-10
COPYRIGHT © 1999 CANON INC.
Control panel
switch ON
SLEEP WMUP WMUPR
Controlled
70˚C
to 70˚C
Initial
activation
Figure 3-302 Heater-On Sequence
Main power Control panel
switch ON power switch ON
SLEEP WMUPR
WMUP
70˚C
Controlled to 70˚C
4.1V
2.9V
1.5
Optimum
sec
value
Intensity
check
The intensity of light is checked by the intensity sensor to
determine the optimum level based on the measurement.
Voltage
Used to stabilize the heat inside the fluorescent lamp while
2.9 V
the lamp is off.
Applied 1.5 sec immediately before turning on the
fluorescent lamp, thereby shortening the time until optimum
4.1 V
intensity is attained.
To stabilize the inside of the fluorescent lamp during
activation.
Table 3-301 Pre-Heat Voltage
Copy Start
key ON
STBY
INTR
Copy Start
Original set key ON
STBY INTR
SCFW
2.9V 4.1V Optimum value
1.5
sec
Continued application of pre-heat voltage
would hinder temperature control;
therefore, it is turned off and on in
conjunction with the scanner heater.
Description
CANON imageRUNNER 600 REV.1 JAN. 2000 PRINTED IN U.S.A.
SCFW SCRV LSTR
Controlled to 70˚C
LSTR STBY
SCRV
Controlled to 70˚C
2.9 V
STBY