CHAPTER
2
Section I. REPAIR PARTS, SPECIAL TOOLS AND EQUIPMENT
2-1. Special Tools and Equipment
maintenance repair parts are listed in TM 5-4940 -
225-34P (when published).
No special tools or equipment are required by
direct support, general support. or depot main-
2-3. Specially Designed Tools and Equipment
tenance personnel.
No specially designed tools or equipment are
2 - 2 . Direct Support, General Support, and
required for maintenance of the shop set by direct
Depot Maintenance Repair Parts
support, general support, or depot maintenance
personnel.
Direct support, general support, and depot
Section Il. TROUBLESHOOTING
2-4. General
probable causes of trouble. The corrective action
recommended is described opposite the probable
This section provider information useful in
cause.
diagnosing and correcting unsatisfactory operation
or failure of the shop set, or any of its components.
2-5. Troubleshooting
Each malfunction stated is followed by a list of
Table 2-1. Troubleshooting
Malfunction
Corrective Action
1. Dynamotor-welder noisy.
a. Interpole coils defective.
a. Repair or replace interpole coils
2. Dynamotor-welder does not
(para 3.15).
develop welding current.
b. Replace compound coils ( para 3-
b. Compound coils defective.
15).
c. Adjust brush spring tension or
c. Welder brushes burned or badly
replace brushes. TM .5-4940-225 -
worn.
120
d. Adjust tension TM 5-4940-225-
d. Brush tension improper.
12.
e. Repair or replace coils (para 3-15).
e. Field coils defective.
f. Clean commutator (para 3-15).
f. Commutator dirty.
g. Replace element (para 3-1.5).
h. Repair or
replace exciter field
coils
h. No excitation voltage to field coil
( para 3-1 5). Adjust exciter brush
(105 to 115 Volts.
tension or replace brushes TM 5-
4940-225-12.
i. Replace armature ( para 3-14).
i. Armature defective,
a. Repair or replace exciter coils
a.. No excitation voltage to rotating
3. Dynamotor-welder does not
(para 3-15 ). Adjust exciter brush
furnish alternating current.
field coils.
tension or replace exciter brushes
TM 5-4940-225-12. Adjust DC
brush tension or replace DC
brushes. Replace armature (para
3-14).
b. Repair or replace rotating field
b. Rotating fied defective.
coils ( para 3-1 5).
c. Repair or replace coils para 3-15 ).
c. Stator coils defective.
a. Repair or replace coils (para 3-15).
a. Stator coils defective.
4. Dynamotor-welder will not
b. Replace armature ( para 3.14).
b. Armature defective.
function as a motor (external
c. Repair or replace switch ( para 3-
c. Main contactor switch defective.
power).
2-1