Epson ColorPage EPL-C8000, Service Manual

Page: 122 / 545

EPSON EPL-C8000 Rev. B
Chapter 2 OPERATING PRINCIPLES 2-61
2.7.8.2 Second Transfer (Belt → Paper)
Transferring the toner image on the belt onto the paper is called 2nd
Transfer. 2nd transfer is done when the HVPS outputs the power to the
Contact Roll.
1. 2nd Transfer Current
The resistance of the 2nd BTR and Back Up Roll changes due to
time and environment. To obtain a stable transfer, it is necessary to
adjust the resistance by adjusting the transfer current. The following
is a flowchart showing how 2nd transfer current is determined.
NOTE: If the output current is not valid, including the case that the 2nd
BTR does not perform advance/retract control because of the
2nd BTR malfunction, it causes the 2nd BTR bad resistance and
a service call error is indicated on the LCD panel.
Figure 2-48. Second Transfer Current Flow
C a l c u l a t e t h e 2 n d t r a n s f e r v o l t a g e a c c o r d i n g t o t h e o u t p u t c u r r e n t
m o n i t o r e d .
N o t e : T h e 2 n d t r a n s f e r v o l t a g e d i f f e r s d e p e n d i n g o n t h e c o l o r m o d e ,
s p e e d m o d e a n d p a p e r t y p e .
A d v a n c e t h e 2 n d B T R A s s e m b l y a n d t h e B e l t C l e a n e r A s s e m b l y
O u t p u t t h e p r e d e t e r m i n e d v o l t a g e t o t h e C o n t a c t R o l l t o m o n i t o r t h e
2 n d t r a n s f e r r e s i s t a n c e .
M o n i t o r t h e o u t p u t c u r r e n t o b t a i n e d f o r m t h e p r e d e t e r m i n e d v o l t a g e
( a s a s u b s t i t u t e f o r t h e r e s i s t a n c e v a l u e ) .
A d j u s t t h e 2 n d t r a n s f e r c u r r e n t a c c o r d i n g t o t h e 1 s t t r a n s f e r v o l t a g e .
D e t e r m i n e t h e 2 n d t r a n s f e r v o l t a g e t o b e u s e d f o r p r i n t i n g .
R e t r a c t t h e 2 n d B T R A s s e m b l y a n d t h e B e l t C l e a n e r A s s e m b l y .