Epson AcuLaser C8500 Service Manual page 142

EPSON AcuLaser C8500
SECONDARY TRANSFER VOLTAGE DETERMINATION TIMING
The secondary transfer voltage determination flow is carried out if any of the
conditions are found to apply when checking conditions during the Cycle Up
Sequence of process control, and is carried out for "D2" seconds "D1" seconds
following the TO signal when process control ends.
2ND BTR ADVANCE/RETRACT CONTROL
2ND BTR must be advanced when secondary transfer is output and must be
retracted at all other times. This is controlled by the BTR CAM CLUTCH and
BTR WHEEL SENSOR.
NOTE: To advance the 2ND BTR, the BTR CAM CLUTCH is ON, and turn
off BTR CAM CLUTCH after you detect the position of the advance
condition with BTR WHEEL SENSOR. To retract the 2ND BTR,
the BTR CAM CLUTCH is ON, and turn off BTR CAM CLUTCH
after you detect the position of the retract condition with BTR
WHEEL SENSOR. (Switched by operation of the FUSER MOTOR
ASSY.)
NOTE: There is very little time between the end of one image and the
beginning of the next. If there is not enough time to execute
"advance"-"retract"-"advance" (When the space of the paper is
under 0.25-second.), it remains the advance condition and output
to the CONTACT ROLL of the HVPS also remains ON.
Operating Principles
Revision C
2-65