Canon NP6317 Service Manual page 186

CHAPTER 10 TROUBLESHOOTING
8. Check the Copy Paper
a. Is copy paper recommended by Canon being used?
b. Has the copy paper absorbed moisture?
Open a now package of copy paper and make copies, then compare the copies.
9. Others
When a copier is brought in to a warm room from a warehouse or other cold area in winter,
particularly when it is being installed, condensation may form inside the copier and cause various
problems.
Examples of problems:
a. The copy image may become light due to condensation in the scanner (lens, mirrors, etc.)
b. The drum may be cold (the electrical resistivity of the OPC will be high), causing the contrast
to be low.
c. Current leakage from the coronas may occur.
d. Paper may jam or fail to be fed satisfactorily due to condensation on the pick-up and delivery
guide plate.
e. The friction of the lower manual feed paper pick-up roller may be reduced, resulting in unsat-
isfactory paper pick-up.
If condensation occurs in the copier, switch the copier ON and leave it to stand for 10 to 20
minutes.
If a cartridge in its original sealed wrapping is taken from a cold place to a warm place and then
immediately unwrapped, condensation may form on it, resulting in image problems. To prevent
this, instruct the customer to leave the cartridge sealed in the room for a sufficient period to allow
it to reach the temperature of the room (between one and two hours) before unwrapping it.
Note:
When detects such as uneven density (differences in the density on the near and far sides of
the copy), lightness or fogging occur first make the adjustments outlined in Basic Image
Adjustment Procedures.
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COPYRIGHT © 1999 CANON INC. CANON NP6317 REV.0 APR. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)