Canon 1000 Service Manual page 132

3. OPERATION AND TIMING
2. Controlling the Drum Surface Potential
a. Outline
The CLC1000 measures the drum surface potential to control the level of the grid and the developing
biases as shown in Figure 3-506. When the power switch is tuned on, the appropriate grid and developing
biases are determined so as to obtain an ideal contrast potential (initial potential control); thereafter, the
appropriate grid bias is determined each time the Start key is pressed, thereby correcting changes over time
(potential correction).
Corrects grid bias (Vg)
See the pages that follow for details of each control mechanism.
The timing of control is as follows:
Initial Potential Control
• If the temperature of the fixing roller is 110°C or less when the power switch is turned ON.
Potential Correction
• Each time the Start key is pressed.
3-88
COPYRIGHT © 2001 CANON INC.
Power switch ON
Determines grid bias (Vg) and
developing bias (Vdc)
Start key ON
Figure 3-506
CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
Initial potential control
Potential control