Xerox PHASER 6121MFP, Service Manual

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Phaser 6121MFP Service Manual 2-17
Theory of Operation
PPM control
PPM (page per minute) control prevents the edge temperature of the heating
roller from increasing during a multi-print cycle using smaller sized media. The
distance between fed sheets is increased according to the number of printed
pages that are to be produced and the media length. This evens out the
temperature of the heating roller and thus stabilizes fusing performance of the
printed toner image.
The PPM control is provided at 20 ppm for a multi-print cycle of producing 20
pages. The number of printed pages per minute is established as detailed below
for each media size for the 21st and subsequent pages.
No PPM control is provided for a multi-print cycle of color printing, as it is 1/4 of
the monochrome printing.
Scanner
Scanner components include:
• Scanner Motor and Drive Belt
• Platen Glass
• Scanhead
Functional components of the Scanner are illustrated below.
The Scanner does not include sensors for determining the size of the original
document. Original media size settings are made on the Control Panel.
Media Conditions PPM
A5, invoice 14 ppm
Media having a narrower width and longer length than above 8 ppm
s6121mfp-114
Scanner Motor (M101)
Exposure Unit