Epson AcuLaser C8500, Service Manual

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EPSON AcuLaser C8500 Revision C
Operating Principles 2-64
PRIMARY TRANSFER VOLTAGE DETERMINATION TIMING
The process of determining primary transfer voltage is executed only during
the Cycle Up Sequence of process control, and is carried out for “C2” seconds
“C1” seconds following the TRO signal as soon as process control ends.
2.7.9.2 Secondary Transfer (Belt-->Paper)
The act of transferring the toner image formed on the Belt to paper is called
“secondary transfer”. Secondary transfer is carried out by output to the
CONTACT ROLL of the HVPS.
SECONDARY TRANSFER DETERMINATION FLOW
The resistance of the 2ND BTR changes according to time and environment. In
order to obtain stable transfer characteristics, variation in resistances
according to time and environment must be offset by adjusting transfer voltage.
Secondary transfer voltage determination flow is as shown on the right.
NOTE: 2ND BTR error is detected when monitor value of output current
for the above and secondary transfer is outside the prescribed
range.
Figure 2-65. Secondary Transfer Determination Flow
2ND BTR ASSY and BELT CLEANER ASSY are advanced.
Monitor environment temperature/humidity, and decide compensation
value by the temperature/humidity.
Output a regulation voltage to CONTACT ROLL, and monitor output
electric current at that time, and decide a standard voltage by the
system residence.
Secondary transfer voltage used for printing is determined.
The 2ND BTR ASSY and BELT CLEANER ASSY are retracted.