e
DC bias voltage level control
The voltage of the DC bias is determined by the signal (DCBC) from the DC
controller.
• High-voltage DC remote signal (DCBTP) = 1
• Roller bias remote signal (ROED) = 1
• Developing DC control signal (DCBC) = 3 V or more or less than 12 V
The above condition turns on the AC bias switch circuit; when the output (DCBC)
from the DC controller PCB increases, the output of DC bias will also increase.
Figure 4-209
4. Roller Electrode Bias Control Circuit
The circuit used to control the roller electrode bias is equipped with the following
functions:
a. Turning on and off the roller electrode.
q
Roller electrode ON signal
• High-voltage DC remote signal (DCBTP) = 1
Roller bias signal (ROED) = 1
Switch circuit goes ON
High-voltage transformer drive circuit goes ON
DC transformer T402 goes ON
The above condition supplies the roller electrode with a bias of about 1000 V; the
DC bias is not controlled to a specific voltage.
DC bias voltage level
DCBC signal input voltage (V)
0
3
11
600
(V)
COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 4 IMAGE FORMATION SYSTEM
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