Canon iR7086, Руководство по обслуживанию

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Chapter 7
7-5
F-7-6
SERVICE MODE:
- COPIER> OPTION> BODY> PO-CNT (enabling/disabling potential control)
0: potential control OFF
1: potential control ON (default)
- COPIER> ADJUST> V-CONT> EPOTOFST (potential sensor offset value input)
If the DC controller PCB has been replaced or the RAM on the DC controller PCB has been initialized, enter the value indicated on the service label.
- COPIER> ADJUST> V-CONT> VL-OFST (VL target potential offset value input)
If the DC controller PCB has been replaced or the RAM on the DC controller PCB has been initialized, enter the value indicated on the service label.
- COPIER> ADJUST> V-CONT> VD-OFST (VD target potential offset value input)
If the DC controller PCB has been replaced or the RAM on the DC controller has been initialized, enter the value indicated on the service label.
- COPIER> FUNCTION> DPC> OFST (potential sensor offset adjustment)
This mode item is part of the series of procedures that must be performed when the potential sensor unit is replaced. It is not performed on its own.
7.4.3 Determining the Optimum Grid Bias
0010-8041
iR7105 / iR7095 / iR7086
The grid bias is determined so that the drum surface potential will be identical to the target potential. (The primary charging bias is set to a fixed value.)
F-7-7
60 min later
Potential
control
Potential
control
Potential
control
Potential control
for transparency
Main power
switch ON
Fixing assembly temperature
(end of fixing assembly warm-up)
[1] The control panel power switch is turned on.
[2] The front door is opened/closed.
Start key ON
Start key ON
10 min later
1 hr later
Starting when the fixing assembly temperature reaches 193 deg C,
executes potential control every 10 min and 60 min.
After previous potential control,
executes potential control every hour.
Potential
control
WMUPR WMUP
STBY
193
198
Potential sensor
Primary charging bias
Grid bias
650 V 550 V or 750 V
Measurement(VD2) Measurement(VD1orVD3) Measurement (target VD)
Vg
550V 650V 750V
VD1
VD2
VD3
Grid bias
Measurements are taken multiple times to
determine the relationship between the drum
surface potential (VD) and the grid bias.
A grid bias (Vg) needed to attain
the target VD is determined.
Potential control sequence started
Charging characteristics
curve
If the target VD is attained using this
measurement, the control is ended;
otherwise, compensatory control is
After measuring VD2, VD1 will be measured
if VD2 is greater than the target VD; if smaller,
VD3 will be measured.