Epson ColorPage EPL-C8000, Service Manual

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EPSON EPL-C8000 Rev. B
Chapter 2 OPERATING PRINCIPLES 2-60
2.7.8 IBT Control
2.7.8.1 First Transfer (Drum
→
Belt)
Transferring the toner image on the drum onto the belt is called the First
Transfer. The First Transfer is done when the HVPS outputs power to
the 1st BTR.
(1) First Transfer Current (Flow)
The resistance of the 1st BTR changes due to time and
environment. To obtain a stable transfer, it is necessary to adjust
this resistance by adjusting the transfer current. The following is a
flowchart showing how 1st transfer current is determined.
Figure 2-47. First Transfer Current Flow
O u t p u t t h e p r e d e t e r m i n e d c u r r e n t t o t h e 1 s t B T R t o
m o n i t o r t h e 1 s t B T R r e s i s t a n c e .
M o n i t o r s t h e o u t p u t v o l t a g e o b t a i n e d f r o m t h e
p r e d e t e r m i n e d c u r r e n t ( 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 )
C a l c u l a t e t h e 1 s t 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 o u t p u t
v o l t a g e m o n i t o r e d .
N o t e : T h e r e a r e t h r e e t y p e s o f 1 s t t r a n s f e r c u r r e n t f o r t h e
o u t p u t v o l t a g e r a n g e s - H i g h , M i d d l e a n d L o w .
A d j u s t t h e 1 s t t r a n f e r c u r r e n t a c c o r d i n g t o t h e D r u m u s a g e .
N o t e : T h e D r u m s u r f a c e c h a r a c t e r i s t i c s c h a n g e s a c c o r d i n g t o u s e .
D e t e r m i n e t h e 1 s t t r a n s f e r t o u s e i n p r i n t i n g .