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Parts marked with "

" is important for maintaining the safety of the set. Be sure to replace these parts with specified

ones for maintaining the safety and performance of the set.

CONTENTS

(Danish)

ADVARSEL !

Lithiumbatteri – Eksplosionsfare ved fejlagtig håndtering.

Udskiftning må kun ske med batteri

af samme fabrikat og type.

Levér det brugte batteri tilbage til leverandoren.

(English)

Caution !

Danger of explosion if battery is incorrectly replaced.

Replace only with the same or equivalent type

recommended by the manufacturer.

Dispose of used batteries according to manufacturer’s instructions.

(Finnish)

VAROITUS

Paristo voi räjähtää, jos se on virheellisesti asennettu.

Vaihda paristo ainoastaan laitevalmistajan suosittelemaan

tyyppiin. Hävitä käytetty paristo valmistajan ohjeiden

mukaisesti.

(French)

ATTENTION

Il y a danger d’explosion s’ il y a remplacement incorrect

de la batterie. Remplacer uniquement avec une batterie du

même type ou d’un type équivalent recommandé par 

le constructeur.

Mettre au rebut les batteries usagées conformément aux

instructions du fabricant.

(Swedish)

VARNING

Explosionsfara vid felaktigt batteribyte.

Använd samma batterityp eller en ekvivalent

typ som rekommenderas av apparattillverkaren.

Kassera använt batteri enligt fabrikantens

instruktion.

The operations of the image forming section are corrected in order to maintain stable and high-quality print even though any changes occur in the
temperature, humidity, consumable parts characteristics, engine conditions, or other environmental conditions.

In concrete, the correction is performed by controlling various control parameters related to the image forming section (process) operations. 

With the above correction operations, stable print quality is always provided, reducing service calls and service works. 

There are following items of the image forming section correction operations (process correction operations).

Image forming section correction operations (process correction operations) list

Item No.

Correction operations

Purpose, effect

Execution conditions, operating timing

1

Image density sensor sensitivity
correction (Calibration) (Gain
adjustment)

Allows the image density sensor to always
detect the correct image patch density. 

Before process correction operation

2

OPC drum marking sensor sensitivity
correction

Allows the OPC drum marking sensor to
always detect the OPC drum marking
normally.

 1

3

Developing bias voltage correction

Prevents against density change and
background copy.

 1

4

Laser beam power correction 1

Prevent against a decrease in print density
due to OPC drum membrane decrease.

Specified rotating time of the OPC drum
(Every 20,000 sec)

Laser beam power correction 2

Outputs the laser beam power
corresponding to the main charger grid
voltage (to maintain the constant voltage). 

Immediately after correction of the main
charger grid voltage (

1)

5

Main charger grid voltage correction 1

Corrects a decrease in the charging voltage
due to the OPC drum membrane decrease,
maintains the correct density of print and
prevent against background copy.

Specified rotating time of the OPC drum
(Every 20,000 sec)

Main charger grid voltage correction 2

Maintains the relations between the
developing bias voltage and the main
charger grid voltage at constant (to prevent
against background copy).

Immediately after correction of the
developing bias voltage (

1)

6

Toner concentration correction

Maintains the normal toner concentration to
maintain the proper density of print and
prevent against background copy.

When the developing bias voltage correction
is performed for the voltage higher than the
specified level is made immediately after the
developing bias voltage correction. (

1)

 1 During warm-up after turning on the power.

During warm-up after cancelling SIM 7-1, 24-7, 25-2, 44-2.
After completion of printing when the accumulated print time reaches 30 min from the previous correction.
When the next print is made when non-print status continues one hour.

The image forming section correction operation (process correction operation) is performed under the following conditions and timing. 

1) During warm-up after turning on the power.

2) During warm-up after cancelling SIM 7-1, 24-7, 25-2, 44-2.

3) After completion of printing when the accumulated print time reaches 30 min from the previous correction.

4) When the next print is made when non-print status continues one hour.

12 – 1

The sensor sensitivity is adjusted to allow correct detection of the OPC drum marking. 

The sensor LED drive voltage (current)  is changed, and when the sensor output voltage reaches the specified level, the sensor LED drive current
control value is stored. In actual operations, the sensor LED is driven by the voltage corresponding to the control value and detection is performed. 

In the developing bias voltage correction, the image sensor sensitivity is adjusted to allow correct detection of the toner image patch density and
normal operation of the developing bias voltage correction. 

The sensor LED drive voltage (current)  is changed, and when the sensor output voltage reaches the specified level, the sensor LED drive current
control value is stored. In actual operations, the sensor LED is driven by the voltage corresponding to the control value and detection is performed. 

Deterioration of photo sensitivity due to deterioration of OPC drum is corrected by adjusting the laser beam power according to the OPC drum
rotating time (operation time) to maintain the correct density print. 

The main charger grid voltage is increased according to deterioration of the OPC drum to maintain the proper density print and prevent against
background copy.

[mW]

Laser beam power

5

10

15

20

25

30

35

Photoconductor drum correction counter

1 count: 20,000sec(Photoconductor drum rotation time)

0.2mW(max)
Laser beam power correction value(

∆  

LPc1)

[v]

Main charger grid voltage correction value

5

10

15

20

25

30

35

Photoconductor drum correction counter

1 count: 20,000sec(Photoconductor drum rotation time)

95v
Main charger grid voltage correction value

12 – 2