Canon imageRUNNER 5065 series Service Manual page 182

Chapter 7
The machine uses VD=390V for both copier and printer control mechanisms.
The timing of potential control is as follows:
Purpose
Operating condition
Operation length
Service mode
Default
2. In the service mode
If enabled in service mode, potential control starts 10 min and 60 min after the main power switch is turned on or when the door is opened and closed. The timing
and particulars of potential control are as follows:
Purpose
Operating conditions
Operation length
service mode
Default
B. Sequence of potential control
1. At the time of warm-up
Drum motor (M1)
Primary charging
Laser
Potential sensor
The sequence and particulars of potential control are as follows:
[1] copier potential control: VD = 8 times max.; VL1 = 8 times max.; VL2 = once
[2] printer potential control: VD = 8 times max.; VL1 = 8 times max.; VL2 = once
SERVICE MODE:
COPIER>OPTION>BODY>PO-CNT (enable/disable potential control)
0: disable potential control
1: enable potential control
2. In the service mode
The following settings may be made for potential control executed 10 min and 60 min after the main power switch is turned on and when the door is opened and
closed: COPIER>OPTION>BODY>PO-CNTMD:
[1] off (default): disable potential control
[2] short mode: decrease the length based on potential attained by executing either of the 2 modes
[3] standard mode: execute both copier and printer potential control in succession
a. Short Mode
The machine executes one of the 2 potential modes, and makes an assumption for the other mode.
For warm-up after power-on, the machine refers to the primary current level, laser output level, and developing bias DC level for both copier potential control and
printer potential control, thereby computing and saving the resulting rate.
In the course of potential control after power-on, the machine executes one of the 2 potential control modes, thus computing the other in relation to the rate it ob-
tained at time of power-on and after power-on.
The following is the sequence of operation used for short mode:
7-4
T-7-3
At time of warm-up
to execute potential control for copier/printer mode
to determine a constant value for copier/printer mode
- the temperature of the fixing assembly is 50 deg C or lower when the main power
switch is on
- when the first image is being formed 60 min after warm-up
10 sec (approx.)
may be enabled or disabled using the following: COPIER>OPTION>BODY>PO-
CNT
ON (potential control for both copier and printer modes)
T-7-4
10 min and 60 min after the main power switch is turned on
to control sensitivity, thus making up for changes in drum temperature
to accommodate changes in charging efficiency
- start of the 1st job 10 min and 60 min after the main power switch has been turned
on
- the door is opened and closed
off: is not executed (default)
short mode: about 5 sec
standard mode: about 10 sec
settings may be OFF, short, or standard as determined by the following:
COPIER>OPTION>BODY>PO-CNTMD
OFF
Fixing assembly temperature 195 C
WMUP
Copier potential control [1]
VD VD VD VL1 VL1 VL2
F-7-6
200 C
WMUPR
Printer potential control [2]
VD VD VD VL1 VL1 VL2
STBY