Operation Manual

62 Chapter 4 - Operational overview
EN
Power system on ECU
The AC, DC, and high-voltage power supply circuits are all contained
within the ECU.
AC power distribution
The AC power circuitry supplies AC voltage whenever the power cord
is connected to the AC power source. AC voltage is distributed to the
DC power supply circuitry and to the AC driver circuitry, which
controls AC voltage to the fuser assembly heating element.
DC power distribution
The DC power distribution circuitry, located on the ECU, distributes
+3.3 Vdc, +5 Vdc, and +24 Vdc as follows:
Overcurrent/overvoltage
There are two overvoltage devices in this printer:
! Fuse F101 provides overcurrent protection for the fusing system
circuitry. Checking or replacing the fuse requires the removal of
the ECU. Fuse F102 provides overcurrent protection to the
printer DC power supply circuitry.
! In addition, the +24 Vdc and +3.3 Vdc power circuitry contains an
overcurrent protection circuit that automatically shuts off the
output voltage when an overcurrent condition occurs as a result
of a short or an abnormal voltage on the load side.
! +3.3 Vdc: Formatter
Laser/beam detect circuitry ECU
Photosensors
! +5 Vdc: Formatter
ECU
Laser/beam detect circuitry
! +24 Vdc: Motor
Exhaust fan
Laser/scanner motor
Document scanner motor
Solenoid
Formatter (routing only)
High voltage power supply
Fuser safety circuit