Xerox Phaser 8500, Service Manual

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4-48 Phaser 8400/8500/8550/8560 Color Printer Service Manual
General Troubleshooting
2 Initial Pumping
Power (watts) Reports minimum pumping
power after start up peak (R1).
This is the first value to reflect
the system pressure. If the
volume is normal (hose/
printhead), then the drop is
large and the pressure rises
slowly. If the volume is small
(hose pinched plugged near
the pump), then the drop is
minimal and the pressure rises
quickly
3 Max Pressure
Pumping Power Reports average pumping
power just before maximum
pressure is reached. May
indicate the efficiency of the
pump, leaks, and/or the setting
of the pressure relief valve.
4 Pumping Time To
Max (sec) Reports the time from pump
on until the pressure relief
valve opens. May indicate the
conditions discussed in R3, as
well as the system volume.
5 No Pressure
Pumping Power
(watts) Reports the average pumping
power after the pressure has
fully decayed. May indicate
pump motor condition/
efficiency.
6 Pressure Decay
Time (sec) Reports the time between
purge valve opening and the
point when the pumping power
(relative to the current
pressure), fades back into the
ripple of the no pressure
pumping power (see the R5
discussion above). This time
could indicate the operation of
the purge valve and the
condition of the bleed orifice
(plugged, etc.).
Purge Pump (Continued)
R# Definition
Typical
Value
(8400) Typical
Value (8500/
8550/8560)
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