Section VI 
i. 
Hold 
the 
drive 
shaft 
to 
the 
left by 
pushing 
(with a 
finger) 
on 
the 
left gritwheel, 
and 
push 
the 
drive 
shaft 
coupler to 
the 
right 
(with 
another 
finger) so 
that 
the 
coupler 
parts 
fit together snugly. 
Tighten 
the 
shaft 
coupler 
clamping 
screw securely. 
j.  Replace all 
parts 
in 
reverse order. 
6-80. 
POWER 
MODULE AND 
TRANSFORMER 
a.  Remove 
the 
top case. Refer to 
Top 
Case 
Removal. 
b. 
Remove 
the 
chassis 
assembly. Refer to 
Printed 
Circuit 
Assembly 
Removal, 
steps 
b. 
through 
f. 
NOTE 
The 
transformer 
is 
held 
in 
place by 
the 
power module molding. 
c. 
Remove 
the 
safety 
earth 
(ground)  wire screw 
at 
the 
left end of 
the 
power module. See Figure 
6-20. 
d.  Disconnect 
the 
three-wire secondary power cable 
from 
the 
printed circuit assembly. 
e. 
Disconnect the primary wires from the transformer. 
f. 
Remove 
the 
screw 
in 
the 
power module. See Figure 
6-20. 
g. 
Lift 
the 
left 
end 
of 
the 
module. 
The 
right 
end is 
held by a 
tab 
which fits 
into 
the 
base 
plate. 
h. 
Replace 
in 
reverse order. 
7475·A·28·1 
When 
connecting 
the 
transformer 
primary 
wires, refer to Section I,  Line 
Voltage 
and 
Fuse 
Selection, for correct 
wiring. 
POWER 
MODULE 
MOUNTING 
SCREW 
Model 7475A 
WARNING' 
To  protect 
against 
possible  electrical 
shock, Be sure 
to 
replace the safety 
earth 
(ground)  wire 
and 
tighten 
the 
screw 
securely. See Figure 
6-20. 
6-81. 
POWER 
MODULE 
WIRING 
6-82. 
The 
power module 
is 
available 
as 
a prewired 
unit 
including 
the 
power 
input 
connector, switch, 
and 
fuse-
holder  (less 
cap 
and 
fuse). 
The 
part 
number 
for 
this 
assembly is 07470-60120. 
This 
does 
not 
include 
the 
power 
transformer. 
It 
is 
recommended 
that 
if 
replacement 
of 
any 
part 
of 
the 
unit 
is 
required, 
the 
entire 
unit 
be replaced. 
However, 
if 
this 
it 
is 
not 
possible 
and any 
part 
must 
be 
replaced  separately, refer to  Figure 
6-21 
for 
the 
correct 
wiring information. 
6-83.  CLEANING 
WARNING  I 
Disconnect 
the 
plotter from 
the 
power 
source prior 
to 
performing 
any 
mainte-
nance.  DO 
NOT 
allow 
water 
to 
run 
onto electrical components 
and 
circuits 
or 
through 
openings 
in 
the 
enclosure 
as 
this 
may 
create a shock 
hazard. 
Do 
not 
attempt 
to clean 
the 
microgrip 
drive  wheels. 
Cleaning 
solutions 
may 
dissolve 
the 
adhesive 
which 
secures 
the 
grit 
particles 
to 
the 
wheels. 
r'\ 
;~SAFETY 
EARTH 
(GROUND) 
WIRE 
SCREW 
Figure 
6-20. 
Power Module Removal 
6-16