Power Supply; Protective Functions - Canon L100 Service Manual

2
Technical Overview > Controller System > Power Supply > Protective Functions

Power Supply

■ Power Supply
Protection
Power
Circuit
Supply
Assembly
3.3V 24V
5V
Generating
Circuit
SW1100
FU101 FU201
FU202 FU203
Engine Controller PCB
24V
3.3V
5.5V
DC/DC
Converter
1.0V
Main Controller PCB
2 Technical Overview > Controller System > Power Supply > Protective Functions
3.3V
Fixing Assembly
Laser Scanner Unit
24V
Pickup Solenoid
(SL1)
24V
Motor Driver PCB
24V
Main Motor
3.3V
(M1)
5.5V
DF Motor
24V
(M3)
3.3V
Control Panel Unit
5.5V
3.3V
CIS Unit
5.5V
F-2-5

■ Protective Functions

● Power protective function
Low voltage power circuit carries the overcurrent preventive function against and overvoltage
preventive function that block the voltage output automatically to prevent the power circuit
brokerage when the overcurrent or overvoltage occur due to load errors such as short circuit
etc.
Thus, when the DC power cannot be output from the low voltage circuit, the protective
function against overcurrent or overvoltage may be working. Turn OFF the Power Switch
(SW1100) to fix load errors and turn ON the Power Switch (SW1100) again (see CAUTION).
Also the circuit carries the 4 fuses (FU101, FU201, FU202, FU203) as another preventive
function. The fuses blow to block the power supply when overcurrent occurs in AC line.
CAUTION:
When restoring the low voltage power after protective function is activated, leave it for
2 minutes or more from turning off the Power Switch (SW1100) or plugging out before
turning ON.
● Safety function
The host machine equips the function of stopping 24V in part of the high voltage power unit to
avoid users and engineers from getting burned or electric shock.
When the cartridge door is opened, the Door Switch (SW501) is turned off and 24V supplied
to the high voltage power unit is shut.
Engine controller CPU determines the door open when the Door Switch (SW501) is turned
OFF.
2-6
2-6