Power Supply Unit - Oki OKIPAGE 24DX Service Manual

2.2 Power Supply Unit

The power supply unit consists of an AC filter circuit, a low voltage power supply circuit, a high voltage power supply
circuit, heater drive circuit, and photosensors.
(1) Low voltage power supply circuit
This circuit generates the following voltages.
Output voltage Use
+5 V Logic circuit supply voltage
+30 V Motor and fan drive voltage and source voltage for high-voltage supply
+8 V Reset circuit, RS232C Line voltage
-8 V RS232C Line voltage
+3.8 V LED HEAD supply voltage
(2) High voltage power supply circuit
This circuit generates the following voltages necessary for electro-photographic processing from +30 V according to
the control sequence from the control board. When cover open state is detected, +30 V supply is automatically
interrupted to stop the supply of all the high-voltage outputs.
Output
Sub-CH -15 uA
CH -1.30 KV
DB -220 V+300 V
SB -450 V
TR +4 KV/-1.3 kV
CB +450 V-1350V
(3) Photosensor
The photosensor mounted on this power supply unit supervises the paper running state during printing.
Figure 2-3 shows the sensor layout diagram.
Service Guide OKIPAGE 24DX/24DXn
Voltage
Voltage applied to Sub charging roller
Voltage applied to charging roller
Voltage applied to developing roller
Voltage applied to toner supply roller
Voltage applied to transfer roller
Voltage applied to cleaning roller
Chapter 2 Operation Description
Use
Page: 12
Remarks
Variable + Only