Canon 7086 Series, Service Manual

Page: 276 / 735

Chapter 7
7-30
F-7-43
7.9.1.2 Correcting the Output to Suit the Environment and the Toner Deposit
0010-8077
iR7105 / iR7095 / iR7086
The separation current output in optimized according to the environment (as identified based on the data from the environment sensor) and the deposit of toner (3
levels: low, standard, high).
F-7-44
DC controller PCB
J510A
J723
J722
AC+DC
J741
J742
J721
J734
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
0 V
24 VH 24 VH
HVDC_REMOTE
HVAC_ON
24VP
GND
GND
HVAC_CNT
HVAC_ON
SEP_DC_CNTR
POST/SEP_ERR
SEP_AC_CNTR
High-voltage DC PCB
GND
GND
1 2 3 4
Relay PCB
4
2
1
1
2
3
4 3
5 5
5
4
3
2
1
High-voltage AC PCB
High-voltage AC transformer
If the current is too high
or too low, '1'.
Voltage input between 0 and 12 V,
used to control the current level of the separation bias.
520 A
The current level of the DC bias varies as
follows according to SEP_DC_CNTR:
3V
11V 12V
SEP_DC_CNT
Separation
charging wire
When'1', high-voltage
DC output is ready.
When '1',
high-voltage A
C output is ready.
When '1', high-voltage
AC output goes on.
12KVPP
8KVPP
The voltage level of the AC bias varies as f
ollows according to the potential of HVAC-CNT:
3V
11V 12V
HVAC-CNT
2
1
17
18
Separ
ation current
(
A)
toner deposit high
toner deposit standard
toner deposit low
If the deposit of toner is too great, the machine
decreases the current level to prevent re-transfer.
If the deposit of toner is limited, the machine
increases the output to prevent separation faults. In a low humidity environment, the paper tends to be dry,
encouraging charges to collect (high resistance).
The machine decreases the output.
Low humidity High humidity