The scanner is slowed down as soon as the signal plate has reached the scanner
original leading edge 1 sensor (PS3); brakes are applied when it reaches the scanner
home position sensor (PS1) so that it stops at its home position.
When stream reading mode is selected with the RDF in use, the scanner original
leading edge 2 sensor (PS4) is used to find out whether the No. 1 mirror mount of the
scanner has reached a specific position.
The distance over which the scanner travels varies according to the size of the copy
paper and the selected reproduction ratio.
2. Relationship between the Scanner Sensors and the Signals
Table 3-301
COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 3 EXPOSURE SYSTEM
3-7
Sensor
Scanner home
position sensor
(PS1)
Original leading
edge 1 sensor
(PS3)
Scanner leading
edge 2 sensor
(PS4)
Signal
SCHP
SCDP1
SCDP2
Description
• Indicates that the scanner is at
home position.
• Indicates that the scanner has
reached a point in home
position.
• Indicates that the registration
clutch has turned on.
• Indicates the scanner forward
distance reference.
• Indicates that the scanner
brakes have turned on.
• Indicates that the scanner has
reached stream reading
position.
Scanner
Forward
Reverse