Canon LBP-1260, Service Manual

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2
A.
Outline
The AC line voltage is supplied to the low-voltage power supply in the power supply by
turning the power switch ON.
The low-voltage power supply circuit generates VDC and VDC. The VDC
supplied to the motor, scanner motor, and exhaust fan to drive them, and to the
voltage power supply PCB. The VDC supplied to the sensors and on the DC controller
PCB.
The VDC consists of two types of voltage: which Is normally supplied from the
power supply, and which is cut when the upper cover is opened and the door switch
is turned OFF.
The block diagram is shown below.
Power supply
DC controller
To fixing roller heater
2-48
B. Protective System
If a short circuit or other fault causes excessive current from the VDC and VDC power
supplies. the overcurrent protection system automatically shuts off the output voltage to
protect the power supply. To reset the power supply after such a shutdown, switch the power
OFF, correct the fault, then switch the power back ON again. If flows through the
AC line, the circuit breaker in the power supply trips and the output voltage is shut off.