Section I 
each 
plotter. 
This 
manual 
applies  directly 
to 
plotters 
with 
the 
serial prefix shown on 
the 
title page. 
1-12. 
If 
the 
serial number prefix of your plotter is higher 
than 
the 
one shown, one  or more  update packages  of 
revised 
pages 
are 
supplied 
with 
the 
manual. 
Use 
these 
new 
pages 
to 
replace 
the 
original pages. 
If 
two 
or 
more 
update 
packages 
are 
supplied, 
insert 
them 
in 
order 
by 
revision letter; 
that 
is, Revision A first, 
then 
Revision 
B, 
etc. 
The 
title 
page 
will 
then 
show 
the 
latest serial prefix 
and 
the 
manual 
will apply directly to plotters with 
that 
prefix. 
1-13. 
In 
addition to plotter changes, revised pages 
may 
correct errors 
in 
the 
manual 
or include improved proce-
dures. 
1-14. 
If 
the 
plotter 
at 
hand 
has 
a  lower serial prefix 
than 
the 
one 
shown 
on 
the 
title page, information 
in 
the 
Product 
History section will 
adapt 
this 
manual 
to 
that 
plotter. 
1-15.  DESCRIPTION 
1-16. 
The 
Model 7475A  accepts digital information to 
produce 
graphic 
plots 
on 
ISO A3, 297 X 420 
mm 
(11 X 
17 
in.) 
paper 
or ISO A4, 210 X 
297 
mm 
(8-1/2 X 
11 
in.) 
paper 
or special transparency plastic. Disposable pens are avail-
able 
in 
various 
ink 
colors. 
1-17. 
The 
six-pen capability permits several colors to 
be used 
in 
a plot 
without 
stopping 
the 
plotter to 
change 
pens 
manually. 
Pens 
are 
automatically  capped while 
they 
are 
stored 
in 
the 
pen carousel. 
1-18. 
Seven different line types 
are 
provided. Labeling 
can 
be done 
in 
nineteen 
character 
sets plus user-defined 
characters. Text (labeling) 
can 
be written 
in 
any 
direction, 
upright, 
or 
slanted. 
Character 
size 
is 
also variable. 
In 
addition, 
arc 
and 
circle generation 
as 
well 
as 
area 
fill 
with 
various fill types 
are 
provided. 
1-19.  LINE VOLTAGE AND FUSE SELECTION 
To 
prevent 
damage 
to 
the 
plotter, 
make 
sure 
the 
line voltage 
and 
fuse selection 
is 
correct before connecting line power. 
I 
WARN•• 
I 
The 
line power cord 
and 
power outlet 
must 
have 
a  protective 
earth 
(ground) 
terminal. 
1-20. 
The 
7475A 
primary 
power circuit 
can 
be configured 
to operate from 
any 
one 
of 
the 
following power sources 
at 
a  line frequency 
of 
48  to 66 Hz, single phase. Maxi-
mum 
power used is 35 
W. 
1-2 
100 Vac-10%, +5% 
120 Vac -10%, +5% 
220 Vac -10%, +5% 
240 Vac -10%, +5% 
Model 7475A 
1-21. 
Line 
voltage 
selection, 
and 
the 
required 
fuse 
ratings 
for 
each 
line voltage setting, 
are 
specified 
on 
the 
line  voltage  label  which is  visible 
through 
the 
small 
recessed window 
in 
the 
rear 
panel. See Figure 
1-2. 
Applying a line voltage of 
220 
V or 240 V 
to 
the 
plotter while 
the 
line voltage selec-
tion is 
set 
for 100 V or 120 V operation 
may 
damage 
the 
plotter circuits. 
1-22. 
The 
line voltage selection 
may 
be changed to con-
form to 
the 
line voltage 
in 
a 
particular 
area. 
Use 
the 
fol-
lowing procedure. 
I 
WARNING 
I 
The 
following procedure should be per-
formed only 
by 
service-trained person-
nel who 
are 
aware 
of 
the 
electrical shock 
hazards 
involved. 
a.  Set 
the 
plotter 
LINE 
switch to 
OFF 
(O) 
and 
dis-
connect 
the 
line cord. 
b.  Remove 
the 
plotter  top  case 
by 
removing 
the 
screws indicated 
in 
Figure 
1-2. 
Lift 
the 
rear 
of 
the 
top case 
and 
the 
front will 
then 
release.  When 
replacing 
the 
top case, 
make 
sure 
the 
PAPER 
HOLD lever extends 
through 
the 
case, 
and 
that 
the 
tabs 
inside 
the 
front 
of 
the 
top 
case 
align 
properly above 
and 
below 
the 
base 
plate. 
c. 
Line voltage selection is determined 
by 
the 
power 
input connections to 
the 
transformer 
primary 
wind-
ings. 
Table 
1-2 
lists 
the 
wire colors 
and 
trans-
former contact connections for 
each 
line voltage. 
The 
transformer 
pin 
numbers 
are 
identified on 
the 
power module molding. Figure 
1-3 
illustrates 
the 
connections for each voltage. 
Change 
the 
wire 
connections 
as 
required 
to 
conform to 
the 
desired 
line voltage selection. 
d.  Make sure 
the 
line fuse  is correct according to 
Table 
1-3. 
The 
fuseholder 
cap 
is 
the 
bayonet 
type. 
Press 
and 
turn counterclockwise to remove, clock-
wise to lock. 
e. 
Change 
the 
position  of 
the 
line  voltage  label 
block so 
that 
the 
voltage selected 
is 
right 
side up. 
This 
block 
snaps 
in 
and 
out 
of 
the 
power module 
molding. 
f. 
Replace 
the 
top case, 
making 
sure 
it 
fits properly 
on 
the 
front edge  of 
the 
base 
and 
the 
PAPER 
HOLD  lever  extends through 
the 
case. 
g. 
Install 
the 
proper power cord for 
the 
power 
range 
selected 
and 
type 
of 
mains 
outlet to which 
the 
cord is to  be connected. 
See 
Figure 
1-4.