Canon NP7160 Service Manual page 100

CHAPTER 4 IMAGE FORMATION SYSTEM
Figure 4-209 shows changes in the developing DC bias in relation to the density of different
originals. If the density of the original is higher (darker) than the Test Sheet and lower (lighter)
than a newspaper, the developing DC bias will vary between F5.0 and F7.5 in terms of Copy
Density lever position.
If the original is lighter than the Test Sheet, copies are made at an F5.0 equivalent (-270 V);
if it is darker than a newspaper, on the other hand, copies are made at an F7.5 equivalent (-400
V).
Developing bias DC (V)
F7.5 equivalent
F5.0 equivalent
4–22
COPYRIGHT © 1998 CANON INC.
Lighter
Test Sheet Newspaper
Figure 4-209
F7.5
Figure 4-210
CANON NP7161/NP7160 REV.0 AUG. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)
Density of original
Darker
F5.0