Xerox Phaser 8400 Service Manual page 161

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
5 CCW Off fe setting
time (sec).
6 Time to CW On
peak fe (sec).
7 CW On peak fe.
8 CW On fe settling
time (sec).
9 CW On average fe.
General Troubleshooting
Typical Typical
Value Value
(8400) (8500/
8550)
0.004 to .015 to
0.15 .20
0.005 to .02 to
0.20 .045
-275 to -.15 to
-10 0.4
-10 to 1 -.04 to
.23
-50 to 15 .02 to .2
Actions
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 may show a dragging or
slow to release clutch.
Reports how long it takes the MP
motor servo system to react to
the sudden addition of the wiper
shaft load.
Larger values may indicate a
slipping or slow to engage
clutch.
Reports the peak effort required
to accelerate the wiper shaft
load.
A smaller value could indicate a
slipping clutch.
Reports the time it takes the MP
motor servo system to "settle
down" following the sudden
addition of the wiper shaft load.
A longer time could indicate a
looseness in the wiper shaft
assembly or a slipping clutch.
Reports the average effort
required to rotate the wiper shaft
in the CW direction at a constant
velocity.
An unusual value could indicate
a difference in the composition
and/or number of the rollers, the
nip pressure, or out of range
mechanical dimensions due to
wear or contamination (such as
paper dust increasing the
effective diameter of a roller).
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