Epson Stylus COLOR 900 Service Manual page 47

EPSON Stylus COLOR 900/900N
I n c o m i n g c u r r e n t p r o t e c t i o n
L
N
T H 1 , T H 2
I n r u s h c u r r e n t t e m p e r a t u r e c o n v e r s i o n
S t a r t i n g r e s i s t o r
M a i n
S w i t c h i n g
Q 1
Q 3 1
H i g h e r h a r m o n i c s a b s o r p t i o n
F 1
R 1
L 1 C 3 , C 4
C 1
T 1
R 2 8
3 0 0 K
C 1 3
F e e d
Q 2
b a c k
Q 3
F e e d
b a c k
P C 1
C o m e s o n w h e n a b n o r m a l .
P h o t o C o u p l e r
4 2 V l i n e c o n s t a n t v o l t a g e c o n t r o l
4 2 V l i n e o v e r v o l t a g e p r o t e c t i o n
Figure 2-9. C265 PSB/PSE Board Block Diagram
S m o o t h i n g
+
D B 1
C 2
C 1 1
F u l l w a v e r e c t i f i c a t i o n
H i g h e r h a r m o n i c s a b s o r p t i o n
+ 5 V R e g u l a t o r
L 5 1
1 7
+
L 4 9 6 0
C 5 4
( I C 5 1 )
5
S m o o t h i n g
D 5 1
Z D 5 3
C 5 1 , 5 2
Z D 5 2
Z D 5 1 ,
Z D 8 7
Z D 8 1 - 8 6
C 8 4
V o l t a g e d r o p d e l a y c i r c u i t a t p o w e r o f f
Chapter 2 Operating Principles
S m o o t h i n g
G L
+ 5 V / 1 . 5 A
+ 5
P S C
+ 5
+ 5
G L
5 V l i n e o v e r v o l t a g e p r o t e c t i o n
G P
+ 4 2 V / 0 . 8 A
+ 4 2
+ 4 2
+ 4 2
G P
+
Q 8 4
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