9-
2-2
INSPECTION
AND
REPAIR
(1
)
ARMATURE
a) Check the diameter of the commutator.
If the out side diamaeter
of
the commu-
tator
is
below
the minimum limit then
replace
it.
Unit
:
rnrn
I
Standard
(New)
I
Limit (Used)
I
30
29
b)
Continuity test for the armature coil.
Use
a
tester to check for continuity
between parallel points on the commutator.
If
There
is
continuity, the armature is still
good.
No
continuity
:
(Disconnected coil)
Replace the armature.
I
Fig.
90
c) Insulation
test
for the armature coil.
Use
21
tester to check for continuity
between a point on the commutator and
the shaft or the core.
If There is no continuity, the armature
is
still
good.
Continuity exists
:
(Short circuited coil)
Replace the armature.
TESTER
I__
Fig.
91
I
TESTER
r
I
1-1
Fig.
92
-
56
-