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AR-350/450 BASIC PROCESS SECTION 5-4

ACTUAL LD POWER(mw) = LD1 +LD2

ACTUAL MC GRID VOLTAGE(v) = -650 + Vg1 + Vg2

ACTUAL DV BIAS VOLTAGE(v) = ACTUAL MC GRID VOLTAGE -(-150)

1

Photoconductor 
characteristics 
correction

Developing 
bias voltage 
correction

Rising 
characteristics 
of 
photoconducto
r potential

When the main charger has not 
been turned on and the 
photoconductor surface 
potential has been decreased, 
if the main charger is turned on, 
the photoconductor surface 
potential will not reach the 
specified level because of the 
rising characteristics of the 
photoconductor surface 
potential. In this case, in order 
to keep the voltage difference 
between the photoconductor 
surface potential rising and the 
developing bias voltage at a 
constant level, the developing 
bias voltage rising is adjusted 
to be the same as the 
photoconductor surface 
potential rising characteristics.

Developing bias 
voltage rising

Photoconductor 
rotation time 
(timer) 
(Stationary 
time)

Photoconductor 
dark potential/
developer 
characteristics 
correction

Developing 
bias voltage 
correction

A decrease in 
the OPC drum 
dark potential 
caused by the 
transfer 
current and a 
decrease in 
the developer 
charging 
capability 
caused by 
deterioration 
of developer

To prevent against dirt on the 
transfer roller and the transfer 
paper guide caused by a 
decrease in the photoconductor 
drum dark potential and a 
decrease in the developer 
changing capacity. (Prevention 
against background copy)

Developing bias 
voltage

Developing 
roller rotation 
time (Timer)

Correction is reset 
when the fuse is 
blown off at 
replacement of the 
developing unit. 
SRU model

Correction is reset 
when the toner 
concentration setup 
diag is executed.

2

Developing 
capacity change 
correction

Toner 
concentratio
n correction

A change in 
developing 
capacity due 
to aging of 
developer 
(Changes in 
developer and 
toner 
characteristics 
(charging 
capacity)) and 
a detection 
error of the 
toner 
concentration 
sensor

To maintain the normal toner 
concentration for changes in 
developing capacity due to 
aging of developer (a change in 
developer and toner 
characteristics (charging 
capacity)) and a detection error 
of the toner concentration 
sensor (Maintaining the proper 
print density and prevention 
against background copy and 
toner dispersion caused by 
overtoner)

Toner concentration 
control reference level 
(data)

Developing 
roller rotation 
time (Timer)

Correction is reset 
when the fuse is 
blown off at 
replacement of the 
developing unit. 
SRU model

Correction is reset 
when the toner 
concentration setup 
diag is executed.

Toner 
concentration 
sensor 
detection error 
caused by a 
change in the 
ambient 
temperature 
(by a change 
in developer 
and toner 
characteristics 
(charging 
capacity))

To maintain the normal toner 
concentration for the toner 
concentration sensor detection 
error caused by a change in the 
ambient temperature and to 
maintain the normal toner 
concentration, and to prevent 
against background copy and 
toner dispersion

Machine 
temperature 
sensor

Item 

No.

Correction items

Factor

Purpose/Effect

Changed item

Correction base 

factor

Correction reset 

conditions

   '     !"#$

AR-350/450 BASIC PROCESS SECTION 5-5

The process correction setup status check described above and the

correction setup can be performed with SIM 44-1. 

The operation status can be set with the bit value below (converted value
from binary to decimal). (Normally all the corrections are operated, and

the setup value is 511.)

In addition, the correction status of each data can be checked with SIM
44-9.

*1 This value is the detected value when PTH is set to 0 by SIM 44-4. If

it is set to other than 0, the set value by SIM 44-4 is displayed.)

The laser output value is corrected in order to provide proper density
prints by maintaining the bright potential at a constant level by correcting

a decrease in the optical sensitivity caused by OPC drum membrane

decrease and optical stress.

This correction is made with the correction value for the temperature

value according to the drum rotation time. A change in the optical

sensitivity of the OPC drum for a change in the temperature is corrected
to maintain the proper print density.  

Vg1

Grid voltage correction value by the drum rotation time

Vg2

Grid voltage correction value by the temperature inside 
the machine

Vb1-1

Vb correction value (First rotation)

Vb1-2

Vb correction value (Second rotation)

Vb2

Developing bias correction value

LD1

Laser power correction value by the drum rotation time

LD2

Laser power correction value by the temperature inside 
the machine

CONTROL

CRUM control specification (1 - 3)

DESTINATION CRUM destination (A - J)
PTH

*1

Process thermister temperature value

T0

Toner control correction value (rotation time correction) 
±100)

T1

Toner control correction value T1 (temperature 
correction) ±100)

T2

Toner control correction value T2 (temperature 
correction) ±100)

0

15

0

14

0

13

0

12

0

11

0

10

0

Vb4 Vb3

9

8

7

LD2

6

LD1

5

Vb2

4

Vb1

3

Vg3

2

Vg2

1

Vg1

0

Bit

SIMULATION 44-1
PROCESS CORRECTION VALUE SETTING. INPUT VALUE 0-511
AND PRESS START.
BIT0:Vg1, BIT1:Vg2, BIT2:Vg3, BIT3:Vb1
BIT4:Vb2, BIT5:LD1, BIT6:LD2, BIT7:Vb3
BIT8:Vb4

511

SIMULATION 44-9
PROCESS CONTROL DATA DISPLAY.
DRUM ROTATION TIME: 

01234567

 (sec)

Vg1: 

30

 (V)

                      Vg2: 

30

 (V)

Vb1-1: 

30

 (V)                       Vb1-2: 

30

 (V)                 Vb2: 

10 

(V) 

LD1: 

0.05

 (mW)

  LD2: 

0.05

 (mW)

CONTROL:

1

  DESTINATION: 

A

         PTH: 

30

 (deg)

TO:  

-5

T1:  

-5

  T2:  

-3

LD POWER CORRECTION

45PPM LD POWER

35PPM LD POWER

Correction limit
(35/45PPMmodel common)

Base level for 
45PPM model

Base level for 
35PPM model

LD POWER CORRECTION

Temperature(    )

Correction value of laser power(mW)

table1
table2
table3
table4

        !"#$

AR-350/450 BASIC PROCESS SECTION 5-6

A decrease in the dark potential caused by OPC drum membrane

decrease and electrical and optical stresses is corrected to maintain the
dark potential on the OPC drum surface at a constant level. (Prevention

against background copy)

This correction is performed with the correction value of the temperature

value according to the drum rotation time.  A decrease in the dark

potential of the OPC drum according to the temperature is corrected to
maintain the dark potential on the OPC drum surface. (Prevention

against background copy)

When the main charger is kept OFF for a long time and the OPC drum

surface potential decreases, though the main charger is turned ON, the
OPC drum surface potential does not rise up to the specified level soon

because of the rise time characteristics of the OPC drum surface

potential. 
In this case, the developing bias voltage rise time is adjusted to the OPC

drum surface potential rise characteristics in order to maintain the OPC

drum surface potential rise and the developing bias voltage at a constant
level. 

This is performed in odder to prevent against dirt on the transfer roller

and the transfer paper guide caused by a decrease in the OPC drum

dark potential and a decrease in the developer charging capacity. 

LD POWER CORRECTION

45PPM LD POWER

35PPM LD POWER

Correction limit
(35/45PPMmodel common)

Base level for 
45PPM model

Base level for 
35PPM model

OPC DRUM ROTATION TIME

MAIN CHARGER GRID

VOLTAGE CORRECTION VALUE(-V)

MAIN CHARGER GRID VOLTAGE CORRECTION FOR

OPC DRUM ROTATION TIME

45PPM

35PPM

MC GRID VOLTAGE CORRECTION FOR TEMPERATURE

MC Grid correction voltage

TEMPERATURE(    )

0v

-650v

-500v

0v

-650v

0v

MC grid
voltage

OPC drum
surface potential

DV bias voltage

-485v

-450v

450v

DV BIAS CORRECTION

DV roller rotation time(sec)

DV Bias correction voltage

1
2
3

   (     !"#$

AR-350/450 BASIC PROCESS SECTION 5-7

The toner concentration control reference level (data) is corrected to

maintain the proper toner concentration for a change in developing
capacity (a change in developer and toner characteristics (charging))

caused by aging of developer and an error in the toner concentration

sensor. 
(Maintenance of proper concentration print and prevention against

background copy caused by over-toner and toner dispersion)

The developing positive bias is applied to the OPC drum at the timing

shown below so that remaining toner on the transfer roller is attracted
again to the OPC drum, performing cleaning. 

1) When the power is turned on:

* No cleaning during the warm up after canceled diagnostic

* However, the cleaning voltage is not applied during warm up after

completion of SIM.

2) After completion of a print job

3) After printing 100 pages (in one job)

<Reference>

OPC drum sensitivity
Changes in the temperature inside the machine and the OPC drum 

This machine employs the toner recycle system to cut the running costs.

The operations of the toner recycle system are as follows:

1) Collects remaining toner (hereinafter referred to as waste toner) on

the OPC drum with the cleaner blade. 

2) Waste toner is transported through the transport pipe. 

3) Waste toner is mixed in the toner cartridge again. 
4) When there is a large amount of toner in the cartridge, waste toner is

simply mixed and stirred in the cartridge. 

5) When there is a small amount of toner in the cartridge, the buffer

plate in the cartridge prevents waste toner from being mixed beyond

a certain ratio.

Note:  If the ratio of waste toner becomes too great, images will be badly

affected as well as developer in the developing unit.

When near empty or empty is displayed, do not shake the toner

cartridge. 
By the way, near empty and empty conditions are stored in the

CRUM-IC in the toner cartridge. 

The toner remaining quantity display is calculated by the accumulated
rotating time of the toner motor (TM). Since, however, there is a

considerable error in the accumulated rotating time of the toner motor,

the status displays of "Toner near end" and "Toner end" which are directly
related to replacement of consumable parts are detected by the toner

quantity sensor. 

"Toner near end" and "Toner end" statuses are stored in the CRUM-IC
and cannot be cleared. 

* The toner supply time clear is set with SIM 24-11. This is not to clear

the counter accumulated in the toner cartridge (CRUM-IC) but to
clear the value read by the machine. It is used when the toner

remaining quantity display is erroneous.

When the toner supply time is 2,500 sec or less, if toner empty is

detected, "F2-02" is displayed to indicate a toner supply abnormality.

TONER CONCENTRATION CORRECTION

TEMPERATURE

CORRECTION LEVEL / TONER CONCENTRATION

CORRECTION RATE

CORRECTION LEVEL(COUNT VALUE)

TONER CONCENTARATION
CORRECTION RATE(%)

CLEANING

READY CONDITION

WARMING UP

PRINTING

CLEANING

1sec

PRINTING(100Sheets)

CLEANING PRINTING(100Sheets)

CLEANING

1sec

1sec

Temperature

OPC drum sensitivity

High

Low

LCD 

display

Remaining 

quantity 

information

Detection

Status

Remark

100 - 
75%

75% or 
above

Toner motor 
rotating time

Normal

75 - 
50%

75% - 50%

Toner motor 
rotating time

Normal

50 - 
25%

50% - 25%

Toner motor 
rotating time

Normal

25 - 0%

25% - 5%

Toner motor 
rotating time

Normal

25 - 0%

About 50 
sheets 
remaining

Toner quantity 
sensor

Toner near 
end

A4 5% output

0%

0%

Toner quantity 
sensor

Toner end

   )     !"#$