Epson Stylus Pro 9000 Service Manual page 50

EPSON Stylus Pro 9000
Paper condition detection
After paper is loaded in the printer, the printer performs the above left,
right, and leading edge detection operations to make sure the paper not
outside of the printable range of the printheads. If any of these edges is
outside of this area, a "Reload Paper" errors.
Basic loading procedure
Make sure the left edge (near the HP) is lined up with the vertical line
of holes in the Lower Paper Guide.
Normal loading area
Paper loaded within 10mm of the center of the vertical line of holes in
the Lower Paper Guide is considered in the printable zone; however,
paper loaded outside that 10mm zone causes an error.
Paper skew
In order to avoid printing on paper that is skewed or fed at a slant too far to
the right or left, the printer detects the right and left edges at the leading
edge of every page. If the printer determines that the paper is skewed 3mm
or more compared to the previous page, a "Paper Not Straight" error
occurs.
Basics
The right and left edge positions are checked at the top of every page.
Degree of skew
Any change in the edge position (from the originally detected position)
over 3mm causes an error.
Operating Principles Printer Mechanism Operation Outline
Revision B
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