Service manual

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6. Details
Pg. Old New/Action
6-11 “S54 Drum Temperature Sensor” Deleted this item.
6-66
4. Readout from the drum potential
sensor is used to adjust:
•
••
•
Development bias (Vb)
• Grid voltage (Vg)
•
Laser diode (LD) power.
4. Readout from the drum potential sensor is
used to adjust:
• Grid voltage (Vg)
• Laser diode (LD) power
6-66 NOTE: These calibrations are used to
determine toner supply, so it is very
important that the developer be
initialized with SP2801 (TD Sensor
Initialization) at installation and when
the developer is replaced.
Deleted this NOTE
6-68
3. Vd should be –800 ± 20V. If it is
within this range, the current value
of Vg will be used for copying. If it
is not within this range, - (Vd +
800)V is added to Vg, and the
process starts again from Step 1.
3. Vd should be –800 ± 20V. If it is within this
range, the current value of Vg will be used
for copying. If it is not within this range, -
(Vd + 800)V is added to Vg, and the
process starts again from Step 1.
Note: VD Correction - As the development
sleeve accumulates toner over time, the
gap between VD and VB decreases, which
makes it easier for dirty background to
occur. To compensate for this, the machine
increases the target VD value to -850
±
±±
±
20V
when the number of copies exceeds the
value set with SP3903: VD Correction
Counter (default: 200K). As a result, VD
increases and the VD-VB gap is maintained.
6-68 4. If Vd cannot be adjusted to this
standard within 5 attempts, Vg is fixed
to –1,000V and SC312 (Potential
Sensor Calibration Error 3) is logged.
4. If Vd cannot be adjusted to this standard
within 5 attempts, Vg is set to the value of
SP2001-001 (default: –900V) and SC315
(Potential Sensor Calibration Error 3) is logged.
6-68 The calibrated ID sensor output will be
used for calibrating the TD sensor
(described below).
Deleted this sentence