Sharp SF-2020 Service Manual page 114

Main code Sub code
44 10 Drum voltage correction drum surface data, patch data display
Used to display the drum surface data and the patch data after execution of the grid voltage after simulation 44-5,
6 or during normal operation is displayed on the copy quantity display.
Since there are two or more display items, the third digit is used to make distinction between the light reception
level and the original judgment level, and the lower two digits are used to display the data.
The display is selected by the magnification ratio key.
The data displayed by the lower two digits are A/D input values of the original sensor, and is expressed in
decimal.
11 Initial grid bias setting
Used to set the initial grid bias in the normal mode, the photo mode, the toner save mode, and the patch
measurement mode.
When this simulation is executed, war-up is started and the currently set normal mode initial grid bias is displayed
on the copy quantity display.
Since there are two or more display items, the third digit is used to make distinction between the light reception
level and the original judgment level, and the lower two digits are used to display the data.
The display is selected by the magnification ratio key.
Enter the set value and press the PRINT button to store the value and start copying. After completion of setting,
press the CA key to cancel the adjustment mode.
12 Copying without grid bias correction
Used to make copying without grid bias correction and drum mark check.
When this simulation is executed, warm-up is started and "A 1" is displayed on the copy quantity display (for
identification of execution of this simulation.)
During warm-up, drum mark check is not performed.
After completion of warm-up, press the PRINT button to start copying.
After starting copying, the grid bias correction is not performed.
The number of multi copy cannot be set. (Single copy only)
After checking the operation, press the CA key to cancel the mode.
(Note) This simulation is used to judge whether the F2 trouble is caused by the grid bias correction or by the
Copy quantity display
3rd digit 2nd, 1st digits
A Measured
data
b
C
d
E
F
Copy quantity display
3rd digit 2nd, 1st digits
1 ∼ 99
A
b
C
d 41
process or the high voltage section trouble.
8 – 16
Content
Display data
(Image density sensor A/D input value)
Drum surface data (patch forming grid voltage) –30V is applied.
Drum surface data (patch forming grid voltage) is applied.
Drum surface data (patch forming grid voltage) is applied.
Patch data (patch forming grid voltage) –30V is applied.
Patch data (patch forming grid voltage) is applied.
Patch data (patch forming grid voltage) +30V is applied.
Display data
Initial grid bias data (normal mode)
Set the grid voltage to 750V.
When the grid voltage is decreased by 1, the voltage is decreased by
5V. When the grid voltage is increased by 1, the voltage is increased
by 5V.
Initial grid bias data (Photo mode)
Set the grid voltage to 750V.
When the grid voltage is decreased by 1, the voltage is decreased by
5V. When the grid voltage is increased by 1, the voltage is increased
by 5V.
Initial grid bias data (Toner save mode)
Set the grid voltage to 750V.
When the grid voltage is decreased by 1, the voltage is decreased by
5V. When the grid voltage is increased by 1, the voltage is increased
by 5V.
Initial grid bias data (Patch measurement mode)
Display value "41" : Set to 410V.
Setting cannot be changed.