HP color laserjet 4500 Manuale Utente
74
Chapter 3 Power supply
EN
High-voltage power supply
The printer contains two high-voltage PCBs mounted in one assembly.
Together these PCBs generate the voltage supplied to the following:
Together these PCBs generate the voltage supplied to the following:
•
primary charging roller
•
developing sleeve
•
primary transfer roller
•
secondary transfer roller
•
ITB cleaning roller
•
upper fusing roller
DC voltage or a superimposed AC voltage and DC voltage is applied to
the primary charging roller, developing sleeve, and ITB cleaning roller.
the primary charging roller, developing sleeve, and ITB cleaning roller.
Positive or negative DC voltage is applied to the primary transfer roller
and secondary transfer roller. Negative DC voltage is applied to the
upper fusing roller.
and secondary transfer roller. Negative DC voltage is applied to the
upper fusing roller.
Protection systems
Problems on the load side, such as short-circuits, can cause an
excessive flow of current from the DC power supplies or can generate
abnormal voltage. When this happens, the excess-current and
excess-voltage protection systems automatically shut off output voltage
to protect the power supplies.
excessive flow of current from the DC power supplies or can generate
abnormal voltage. When this happens, the excess-current and
excess-voltage protection systems automatically shut off output voltage
to protect the power supplies.
If the protection systems are activated and the power supply circuit
does not output DC voltage, turn the printer off, correct the problem in
the faulty load, and then turn the printer on again.
does not output DC voltage, turn the printer off, correct the problem in
the faulty load, and then turn the printer on again.