Xerox Phaser 8400 Service Manual page 163

Tray 1 Pick Shaft (Continued)
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
2 Initial average MP fe.
(mpts).
3 Transition MP fe min.
(mpts).
4 Contact average fe.
5 Pushdown MP fe
max.
6 Final average MP fe.
(mpts).
General Troubleshooting
Typical Typical
Value Value
(8400) (8500/
8550)
-1 to
1400
750 to
1800
120 to
2000
750 to
2000
900 to
1500
Actions
Reports the average MP fe
immediately following the pick
shaft engagement.
A higher value of R2 could
indicate extra friction between
the cams and the lift plate
followers (wear, contamination,
etc.), as well as high lift plate
spring tension or higher shaft
bearing drag. Also, if the missing
tooth gear did not kick forward
and engage, this value would be
unchanged from R0.
Reports the minimum MP fe
value at the transition point
between breaking separator pad
contact and the continued
depression of the lift plate.
Value reflects the effort needed
to rotate the pick shaft and
compress the lift spring. A higher
value of R3 could show higher
cam/bearing friction and/or lift
plate spring strength.
Reports the average MP fe while
the pick roller is contacting the
separator pad. This value should
reflect the coefficient of friction
between the separator pad and
the pick roller. This value may be
effected by contamination or
glazing.
Reports the peak MP fe during
the interval when the pick cams
are depressing the lift plate.
A higher value here could
indicate issues with the cam
surfaces or the spring
compression force.
Reports the average MP fe
following the re latching of the
missing tooth gear.
This value should be the same
as R0 if the missing tooth gear
successfully relatched.
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