TM 55-2925-236-40
FINAL TEST PROCEDURES
troubleshooting table 4-1, disassemble, and re-
4-1. General
peat inspection procedures as outlined in Section
If the starter generator fails to meet any of
the test requirements and visual inspection does
not disclose the cause of the trouble, refer to the
from the beginning.
Table 4-1. Troubleshooting
Item
Trouble
Probable Cause
Remedy
1
Short Brush Life or Excessive
Replace, Service, and/or Readjust
Worn, Improperly Seated, or Loose
Sparking
Fitting Brushes
Brushes as Necessary.
Low Brush Spring Tension
Readjust and/or Replace Spring.
Dirty Commutator
Service Commutator.
Scored, Pitted, or out-of-round
Resurface Commutator.
Commutator
Short, Ground, or Open Armature
Replace Armature,
Ball Bearings Worn
Replace Ball Bearings.
Shorted Compensating Winding
Replace Yoke Assembly.
Generator Noisy
Faulty Condensers
2
Replace Condensers.
Discharged Battery
Replace Battery.
Excessive Sparking at Generator
See Item 1.
Brushes
Output Voltage Low or no
Shorted or Open Rotor or Exciter
Test; if Faulty, Replace Rotor and/or
3
Reading
and/or Shorted or Open Diodes
Diodes.
control Panel Faulty
Replace Control Panel.
Shorted and/or Open Output
Test; Replace Housing if Necessary.
Windings
Drive Inoperative
Check Drive.
Output Voltage Indicates
Control Panel Faulty
Replace Control Panel.
4
High
Make Proper Connections and/or
Wrong or Faulty Connection Between
Generator and Control Panel
Tighten Connections.
Output Voltage Erratic or
Faulty Control Panel
5
Replace Control Panel.
Fluctuates
High Resistance, Internal or External
Clean and/or Tighten Connections.
Connection in the dc Connection
of Generator
Intermittently Shorted, Grounded,
Test; Replace Rotor and/or Housing
or Open ac Rotor and/or Stator
if Necessary.
Output Phase Sequence
External Wiring Not Properly
Check External Wiring. Make Proper
6
Incorrect With Generator
Connected
Connections. (Refer to External
Rotation Correct
Wiring Diagram.)
System Meters Indicates
External Wiring Not Properly
Check External Wiring. Make Proper
7
Zero, Low, or Fluctuating
Connections and Tighten.
Connected
Improper Adjustment of Voltage
Reading (Output Voltage
Check Adjustments. Make Proper
Adjustments.
satisfactory)
Regulator
Flash Field in Proper Direction.
Generator Field Magnetized in
System Meters Read Off
8
Scale in Wrong Direction,
Wrong Direction
External Wiring Not Properly
with Generator Connected
Refer to Wiring Diagram. Check All
to Load
Connected
Wiring Connections. All Connections
Should be Clean and Tight.
Equipment Operating Un-
Faulty Control Panel
Replace Control Panel.
9
Improper Frequency
satisfactorily Although No
Check Drive.
Load Voltage is at Proper
Value
10
Generator Overheats
Excessive Load
Check and Reduce Load, if Necessary.
