OM-2245 / Operation and Maintenance Manual
ITW GSE 4400 / 400 Hz. Generator Set
March 15, 2015
Chapter 2-4
Page 10
Generator
Trouble, Symptom,
Condition
Probable Cause
Test, Check, and/or Remedy
1.
No (or low) voltage output
a.
Shorted diode in exciter
rectifier (CR2).
Check diodes in accordance with Chapter
2-3 Section 4 and 5. If diodes are good,
proceed to step b.
b.
Open or shorted exciter rotor
winding (G2).
Use ohmmeter to check for open or
shorted condition diodes in accordance
with Chapter 2-3 Section 4 and 5. If
exciter rotor windings are good, proceed to
step C.
c.
Open or shorted exciter field
windings (L2).
Check field resistance. See Chapter 2-3
Section 4 for normal values.
d.
Open or shorted generator
rotor windings (L1).
Check resistance with ohmmeter to
determine if open or short circuited diodes
in accordance with Chapter 2-3 Section 4
and 5.
2.
Generator operates
single phase.
a.
Open or short circuited
winding in generator stator
(G1).
Check stator-winding resistances. See
Chapter 2-3 Section 4 for normal values.
3.
Generator overheats
a.
Loose connection causing
high resistance.
Check all output connections. Look for
discoloration caused by heat. Tighten or
replace as required.
b.
Improper or blocked
ventilation.
Check for foreign material (rags, etc.)
blocking airflow. Provide adequate
ventilation.
c.
Generator stator windings
short circuited.
Check stator windings. See Chapter 2-3
Section 4.
4.
Unbalanced output
a.
Loose connection in output
circuit.
Check all output connections. Discolored
connectors indicate a loose connection.
Tighten or replace as required.
b.
Open or short-circuited
phase.
Check stator windings in accordance with
Chapter 2-3 Section 4. Repair or replace
as required.
c.
Defective connection in
output circuit.
Check the plug and receptacle connectors
at aircraft. Tighten, repair, or replace as
required.
d.
Break or cut in output cable
assembly.
Inspect the output cable for damage.
e.
Unbalanced load.
Check the aircraft 400-Hz components.
