Service manual

1.3.11 V
D
, V
B
, V
L
Selection (Pointer Table)
The machine now adjusts V
D
, V
B
, and V
L
to try to bring V
DP
to the ideal
value. To do this, it uses a pointer table. This is a "look-up" table in memory
of V
DP
against predetermined values which is compared V
D
, V
B
, and V
L.
The machine takes the value of V
DP
calculated in the previous section, and
"looks" for the value of V
DP
in the pointer table that is closest to this. The
machine reads the preset values of V
D
, V
B
, and V
L
that are in this row of the
pointer table.
1.3.12 V
G
, V
B
, I
LD
Correction
The machine will then use these predetermed values of V
D
, V
B
, and V
L
during copying until the next process control self check. These values are
designed to bring the actual V
DP
values to the optimum value for the
machine’s current condition.
•
V
D
: Drum potential without exposure - to adjust this, the machine adjusts
the charge corona grid voltage (V
G
)
•
V
L
: Drum potential with the strongest exposure - to adjust this, the
machine adjusts the laser diode input current (I
LD
)
•
V
B
: Development bias
1.3.13 Confirmation Procedure
The calculated V
D
and V
L
are target potentials for maintaining optimum copy
quality. However, residual voltage is not included in these potentials. To
correct for this, the machine corrects the actual V
D
and the actual V
L
.
If V
D
cannot be adjusted to within 5V of the target V
D
after 40 attempts, the
previous V
D
is used, and the SC code counter is incremented. No error
condition is indicated on the the LCD panel
PROCESS CONTROL
A166/A187/A189 2-10 SM
CÓPIA NÃO CONTROLADA
CÓPIA NÃO CONTROLADA