Canon Color imageRUNNER C5180 Series, Service Manual

Page: 179 / 851

Chapter 6
6-12
F-6-15
6.3.3.2 Scanning Lamp
The machine's scanning lamp is a xenon lamp, which uses xenon gas sealed inside. On the outside of the glass
tube, 2 electrodes are arranged in parallel with the tube; the inside of the tube, on the other hand, is coated with
fluorescent material. When a high-frequency high voltage is applied to the electrodes, the gas inside the tube
starts to discharge, causing the fluorescent material to emit light.
F-6-16
6.3.3.3 Turning On and Off the Scanning Lamp
The scanning lamp is turned on and off by the drive signal (LAMP_ON) generated by the CPU of the reader
control PCB. When the signal is generated, the inverter PCB generates high-frequency high voltage in the
activation control circuit using the drive voltage (+24 V) supplied by the reader controller PCB to turn on the
xenon lamp.
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Relevant Error Code:
E220 (Lamp ON fault when the power is ON.)
Inverter PCB fault, reader controller PCB fault, or scanning lamp fault.
6.3.4 Detecting the Size of Originals
6.3.4.1 Identifying the Size of Originals
The machine identifies the size of an original based on combinations of measurements taken of the light
reflected by specific points (using a reflection type sensor and CCD). In consideration of possible displacement
of the original when the ADF is closed, the machine uses a 2-point CCD check.
- Main Scanning Direction:
by CCD (AB-configuration; 8-point measurement; inch-configuration, 6-point measurement)
- Sub Scanning Direction:
reflection type photo sensor (AB-configuration: 1-point measurement; inch-configuration: 1-point
measurement)
Inverter PCB
Xenon lamp
Activation
control circuit
J601 J206
Reader controller PCB
LA1
CPU
GND
GND
GND
GND
XE-ON
24V
24V
XSYNC
24V
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
fluorescent
medium
electode
opening
electode
electode
electode
glass tube