Sharp SF-2050 Service Manual page 85

4. Copy density adjustment
(1) When the copy density adjustment is required:
The copy density adjustment must be performed in the following
cases:
•
When in maintenance
•
When the charging/transfer charger output current and the separa-
tion charger bias voltage and the grid voltage are adjusted. (When
the charger unit and he high voltage unit are replaced.)
•
When the developing bias is adjusted.
•
When any part in the AC PWB unit is replaced.
•
When AE sensor is replaced.
•
When the copy lamp is replaced.
•
When the optical unit is replaced.
•
When the optical unit is disassembled, repaired, or adjusted.
•
When the exposure adjustment plate is moved.
•
When the drum is replaced.
•
When the main PWB is replaced.
(2) Note for copy density adjustment
Before the copy density adjustment, perform the following items.
1
Clean the optical system (the table glass, the lens, the mirrors, the
copy lamp. the reflector).
2
Clean the AE sensor. (With a cloth immersed with water or al-
cohol, clean the photo sensor surface.)
(Note: If the photo sensor surface is cleaned with a dry cloth,
static electricity is produced to attract dusts.)
3
Clean the charger wire (transfer/separation) and the screen grid.
4
Clean the blank lamp and the discharge lamp around the drum
holder.
5
Clean the drum cleaning blade. (After cleaning, be sure to apply
starting powder.)
•
(Note) First perform the manual exposure copy density adjust-
ment, then perform the auto exposure copy density adjust-
ment. Do not reverse the sequence.
•
This model performs the correction to the optical system
dirt automatically.
When simulation 46 is executed, the correction in each
mode is set to the initial state. When simulation 46 is
executed, adjust in all exposure modes.
•
This model performs the correction against decreasing
sensitivity by long use automatically. When simulation 24-
07 is executed, the correction is set to the initial state.
Execute simulation 24-07 before executing simulation 46-
01.
(3) Preliminary arrangement for the copy density
adjustment
(1) Initial setting of AE copy density level
1
Enter the key operator code.
2
Execute program No. 20.
The LCD shows the following display.
P.20: AUTO EXPOSURE ADJUST.
1. LIGHTEST
4. DARKER
3
Select "3" with the 10-key pad.
4
Cancel the set mode with the CA key.
(2) TSM mode initial setting
1
Execute program No. 22.
P22: TONER SAVE MODE.
1. YES
2
Set the mode to the toner save mode with the 10-key pad.
8 – 19
2. LIGHTER 3. NORMAL
5. DARKEST
2. NO