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IWQ Series Service Manual
4.2 Electric Concerns
4.2.1 Block diagram
M
a
in
b
o
a
rd
P
-932-
Fl
uo
re
sc
en
t i
ndi
ca
to
r
tube #
1
Fl
uo
re
sc
en
t i
ndi
ca
to
r
tube #
2
Ta
cti
le
ke
y
Bu
zze
r
Func
tiona
l
gr
ound
ing
RS
-232C i
nput
/out
put
jo
ur
na
l
pr
int
er
/loud
buz
ze
r
I/F
b
o
a
rd
P
-93
4-1
(O
pt
ion)
Phot
o c
oupler c
irc
uit
EH
7 XJ
4
A
/D
boa
rd
P
-933
PM
5.
08/
4/
90 (
Ter
m
ina
ls)
Func
tiona
l
gr
ound
ing
Pr
ot
ec
tiv
e
gr
ound
ing
Pr
ot
ec
tiv
e
gr
ound
ing
W
at
er-p
ro
of
lo
ck
L
oad c
ell
W
at
er-p
ro
of
lo
ck
Func
tiona
l
gr
ound
ing
SW
power
s
up
pl
y
Po
wer
s
upp
ly
sw
itch
in
g
Fr
on
t ca
se
R
ea
r ca
se
AC
P
ow
er