Canon imagePRESS C1 Service Manual - page 366
Chapter 7
7-17
The following figure indicates the relationship between the environmental change and the target contrast potential.
F-7-17
4. Setup of Grid Bias and Developing Bias
Based on Vd, VL and target contrast potential found with the drum surface potential control, determine the grid bias and the DC developing bias.
First, for eliminating the overlap, draw a line for the developing bias DC (Vdc) at the point where Vback voltage is added to Vd. (The Vback voltage is determined
as 148-165V by the water amount that is measured with the environment sensor.) Then, find out the point where the value of the contrast potential between Vdc
and VL indicated in the following figure is the same as of the target contrast potential, and obtain the target values of the grid bias and the developing bias from the
point.
F-7-18
The measured data of the surface potential can be checked with DISPLAY > DPOT after executing the service mode (FUNCTION >DPC > DPC).
The target values in the field are indicated below.
7.4.6 ATVC Control
0013-3674
imagePRESS C1 P / imagePRESS C1 / imagePRESS C1+ (Printer) / imagePRESS C1+
When transferring toner from the photosensitive drum to the ITB, from the ITB to a paper, the ATVC control is executed to determine the appropriate transfer
voltage.
The ATVC control has the following two control types: the primary transfer ATVC and the secondary transfer ATVC.
Screen Display
Target Value
V00-500V
-450V
V00-800V
-730V
VFF-500V
-180V
VFF-800V
-300V
1
10
20
400
300
200
(V)
(g)
Amount of water
Target Contrast Potential
(V)
(V)
Vd
Vback
Vdc
VL
-520V
-370V
Target Contrast Potential
Grid Bias
Drum Surface Potential /
DC Developing Bias