Canon SORTER S-82 Service Manual page 45

III. POWER SUPPLY
A. Outline
The power supply unit employs a remote switch system.
When the printer is turned ON, the printer outputs a command to the option controller via
the video controller. The option controller outputs a POWER-ON signal (PWRON-IN) to the power
supply unit via the sorter driver according to this command to turn ON the power. The power
supply unit supplies +24V and +5V to the sorter driver when the PWRON-IN signal is "H."
+24V is used for driving the feed motor and solenoids. +5V is used for sensors and ICs on
the sorter driver PCB.
The power supply unit is provided with a stand-alone mode switch which allows the unit to
turn ON/OFF the power without POWER-ON signal (PWRON-IN) and to perform the Service
mode.
The block diagram is shown below.
Stand-alone
mode switch
Noise
filter
B. Protective Function
The +24V and +5V power supply circuits each have overcurrent/overvoltage protective functions
which cut off the output voltage when troubles, such as short-circuit, occurred on the load side
and resulted in abnormal voltage or overcurrent flow, to prevent failure of the power supply cir-
cuits.
Therefore, if the overcurrent/overvoltage protective functions are activated and no DC voltage
is output from the power supply circuit, turn OFF the power switch of the printer, rectify the
trouble on the load side and then turn the power switch ON again.
Power supply unit
Remote
contorol
Smoothing Trans-
circuit
former
circuit
Overcurrent
protection
curcuit
Figure 2-3-1
PWRON-IN
+24V
Smoothing Sorter
circuit
driver
+5V
Overvoltage
protection
curcuit
CHAPTER 2
PWRON-IN
Option
controller
+5V
Sensors
+24V
Solenoids
+24V
Motor
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