User guide

EN Printer functions and operation 89
Overcurrent/overvoltage
There are two overvoltage devices in this product:
 Fuse F101 provides overcurrent protection for the fusing system
circuitry.
 Fuse F102 provides overcurrent protection to the printer DC
power supply circuitry.
You can check or replace the fuses by removing the back cover
(page 164).
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. These circuits automatically
reset.
High-voltage power distribution
The high-voltage power supply applies an overlap of DC and AC
voltage to the primary charging roller and the developing roller. This
circuit also applies a positive or negative DC voltage to the transfer
roller according to the instructions from the engine control unit.
This circuit also controls the image density by changing the primary
AC voltage and the developing AC bias according to the print density
setting.