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Service Guide
23
Phaser 840 and Phaser 850 printer differences
Summary of differences between Phaser 840 and Phaser 850
Phaser 850 unique part
Details
Main board
The main board is based on a 603E processor at 200 MHz. It
features a new rear panel with built-in10/100BaseT and no
SCSI port or riser card. The large Dallas NVRAM chip is no
longer used. Also the RAM connectors are angled. A battery
on the main board will support the real-time clock (10 year
life). The printer supports up to 256 Mbytes of RAM. Only a
Token Ring Card and an IDE Internal Hard Drive are available.
Power control board
Improved fusing. Resettable fuses (by disconnecting AC
power) on +5v and +40v Hi-capacity Paper Tray leads. No x-
axis fuse.
RAM DIMMs
Unlike the Phaser 840 printer, the Phaser 850 printer is not
as restricted on the height of the RAM DIMMs the main board
will accept since it uses angled RAM DIMM connectors.
Printhead
The Phaser 850 printer uses the same printhead as the
Phaser 840 printer. However, the printhead mount has been
factory calibrated so no head-to-drum adjustment is required
when installing the printhead (as long as the printhead’s four
mounting screws have not been loosened nor the printhead tilt
setting altered on the left side of the frame).
Y-axis idler pulley
The Y-axis belt drive assembly now features a built-in spring
tension. A Y-axis belt tension tool is not required.
Cap/wipe/purge assembly
This is a new assembly. It also uses a new mounting system
that does not require the disassembling of the timing belts in
order to remove the cap/wipe/purge assembly
Preheater entry flags
New sensor flags, less prone to snagging paper when
jammed paper is pulled from the printer, are mounted on the
upper feed roller assembly.
Drum maintenance clutch
A new clutch is used in the Phaser 850 printer.
Left I/O board
A new left I/O board is used in the Phaser 850 printer.
Y-axis drum encoder assembly
A new Y-axis drum encoder is used with the Phaser 850
printer. It does not use a separate drum home sensor.
Lower stripper blade holder
and stripper blade
The lower stripper fingers of the Phaser 840 printer have been
replaced with a replaceable stripper blade, called a rapid
release guide, and a guide holder.
Rollers and clutches
Phaser 850 roller shafts are re-tooled for clutches with C-clips
instead of the Phaser 840 printer’s snap-fit feature. The parts
are reversed compatible only if the shaft, clutch and e-ring
combination replace the Phaser 840 parts.
The bushings for the Phaser 850’s duplex roller are installed
with C-clips from the inside of the chassis.
Preheater
A new paper preheater designed to accommodate the travel
of the paper preheater entry flags is used in the Phaser 850
printer. The preheater is reverse compatible into the
Phaser 840 printer.
Inks
The Phaser 850 printer uses new inks using a different
formulation. The inks are not compatible with a Phaser 840
printer. Likewise, Phaser 840 inks are not usable in a Phaser
850 printer.
Summary of Contents for Phaser 840
Page 11: ...xii Phaser 840 and 850 Color Printers ...
Page 65: ...54 Phaser 840 and 850 Color Printers ...
Page 101: ...90 Phaser 840 and 850 Color Printers ...
Page 125: ...114 Phaser 840 and 850 Color Printers ...
Page 134: ...Service Guide 123 Clearing PostScript NVRAM menu item ...
Page 135: ...124 Phaser 840 and 850 Color Printers ...
Page 166: ...Service Guide 155 Figure 1 Cabinet FRUs 7 5 6 8 1 2 4 0388 21 3 9 9 ...
Page 170: ...Service Guide 159 Figure 3 Paper path FRUs 0388 80 2 1 5 11 10 9 12 6 4 3 7 13 8 11a 11b ...
Page 172: ...Service Guide 161 Figure 4 Motor and fan FRUs 0388 14 7 4 3 5 6 2 1 ...
Page 174: ...Service Guide 163 Figure 5 Circuit board FRUs 4 3 5 2 1 9 7 6 8 10 11 13 0388 81 12 7a ...
Page 176: ...Service Guide 165 Figure 6 Solenoid and clutch FRUs 4 5 3 2 1 0388 23 ...
Page 182: ...Service Guide 171 Figure 9 High capacity PaperTray 0388 65a 1 2 ...