Media Size Detection; Sensor For Media Size Detection; Size Sensors; Tray Lifting - Lexmark W840 Service Manual

4024-XXX

Media size detection

Media size is automatically detected by loading media in the tray and by the rear media edge guide that is
attached to the media tray assembly and aligned with the side of the media. The position of the rear media edge
guide is detected by the sensor (HCF media size L) and the sensor (HCF media size R).
Media size
B5L
7.25" x 10.5" L
8.5" x 11" L
A4L
Note: B5L and 7.25" x 10.5" L can be switched by the NVM.
Sensor (HCF media size R)
Detection of media size is carried out during the startup procedure and when a specified time has passed from
the sensor (HCF media tray set) level change "off to on" with the tray inserted. Media size is also detected at
every constant time. When the same size has been detected at specified times consecutively, the size of media
loaded in the tray is determined.
If a sensor level pattern does not match the above table, media size cannot be determined. In this case, though
the tray is lifted, print start by feeding media from the tray is inhibited.

Sensor for media size detection

Size sensors

There are two size sensors: sensor (HCF media size R) and sensor (HCF media size L).
By moving the HCF rear media edge guide to turn on/off these sensors and by using the sensor level patterns,
media size can be determined.

Tray lifting

Tray lift operation starts automatically when the HCF media tray is inserted with media loaded.
Media is lifted and stops at the feeding position. At the same time, detection of no media and remaining media
volume becomes available.
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Options Service Manual
Sensor (HCF media size R) Sensor (HCF media size L)
off
on
off
Sensor (HCF media size L)
off
off
on
HCF rear media guide