Xerox Phaser 8400 Service Manual page 162

Wiper Shaft (Continued)
Runs the media path drive train and engages the head maintenance clutch on the fly then
disengages the clutch. The test is repeated in both directions to determine clutch characteristics,
steady state drive requirements, bearing status, etc.
R# Definition
10 CW On fe ripple.
11 CW Off fe settling
time (sec).
Tray 1 Pick Shaft
Runs the media path drive train and engages the tray 1 pick solenoid on the fly. The pick shaft
goes through two full revolutions while drive requirements are determined.
R# Definition
0 Off average MP fe.
(mpts).
1 On response time.
(sec).
4-22
Typical Typical
Value Value
(8400) (8500/
8550)
20 to 75 0 to .4
-5 to .01 .02 to .22
Typical Typical
Value Value
(8400) (8500/
8550)
800 to
1500
-1.5 to
0.95
Phaser 8400/8500/8550 Color Printer
Actions
Reports the variation of effort
needed to rotate the wiper shaft
in the CW direction at a constant
velocity.
A larger value may show
particles in the gears or non
uniform contamination of a roller
(causing a lump).
Reports the time it takes the MP
motor servo system to "settle
down" after the sudden release
of the wiper shaft load.
A larger value could indicate a
dragging or slow to release
clutch.
Actions
Reports the average MP fe
during the run in interval before
the pick shaft is engaged.
Reports the time between pick
solenoid activation and a
detectable response from the
MP drive system indicating that
pick shaft engagement. A higher
value of R1 could indicate that
the missing tooth gear engaged
more slowly than usual, which
could be a problem with the lift
plate spring tension, the
condition of the sliding surfaces
between the cams and the
followers, drag on the pick shaft,
or problems with the drive gears
(missing teeth, etc.).