TM 5-6115-271-14
TO 35C2-3-386-1
TM 05926A-14
NAVFAC P-8-613-14
Table 4-2. Troubleshooting (Cont `d.)
Table 4-2. Troubleshooting (Cont 'd.)
MALFUNCTION
MALFUNCTION
TEST OR INSPECTION
TEST OR INSPECTION
CORRECTIVE ACTION
CORRECTIVE ACTION
3. GENERATOR FAILS TO BUILD UP RATED
Step3. Inspect the field flash switch for cracks,
breaks, loose terminals and other
VOLTAGE (Cont'd)
damage. Test by activating the field
Step 2. Check the voltage regulator for loose
flash switch. If the field flash switch
wires, corrosion, metal to metal con-
does not work, manually flash the field
tact, or incorrect wiring.
as follows:
Refer to intermediate (field) (direct
support and general support) main-
a. Open or remove the control box
tenance personnel.
cover (para 4-15).
b. Connect two 1.5 volt flashlight
meter and voltage selector switch for
batteries in series and connect a wire
broken glass, improper operation, or
to each end.
other damage. Test the frequency
c. Connect the positive wire from
meter, load meter and voltage selector
the batteries to terminal No. 20 on the
switch as follows:
voltage regulator.
a. Frequency Meter.
d. Start the generator set (para
(1) Remove load cables and start
2-2b).
generator set.
e. Momentarily touch the negative
(2) With a multimeter, measure
wire to terminal No. 21 on the voltage
DC Current across the terminals of
regulator to flash the field.
the frequency meter. This reading
If the field can be flashed manually,
will be in DC micro amperes. Read-
replace the switch (para 4-20).
ing at minimum deflection at full
3. GENERATOR FAILS TO BUILD UP RATED
scale valve will be 0 to 200 micro
VOLTAGE
amperes. Normal reading at 60 Hz
or 400 Hz will be 90 to 110 micro
Step 1. Inspect the variable resistor for cracks,
amperes.
corrosion, loose connections and other
damage:
(3) If reading is not within
Test the variable resistor as follows:
specifications, stop the generator and
connect a frequency meter of known
accuracy in series with the set fre
nect terminal 26 of the voltage regulator
quency meter. Be sure to observe
terminal board.
polarity.
(4) Restart the generator set and
tance across the variable resistor
compare the reading on the set meter
terminals by varying the resistor from
and test meter. Frequency variation
full counter-clockwise to full clock-
between these two meters should not
wise position. This reading should
exceed 1%.
move smoothly from 0 to 750 ohms
If the frequency variation
10% as the variable resistor is rotated
exceeds 1% of full value, replace the
to the full clockwise position.
frequency meter (para 4-17).
NOTE
On sets manufactured prior to 1968, this reading
will be 0 to 250 ohms 10%.
Replace the variable resistor (para 4-16)
if the reading is not within specifications.
Change 10
