k. For a trial setting adjust the voltage regulator to
b. When the main engine is running the auxiliary
hold a constant voltage, at both idling and full throttle
generator supplies the current needed for lights and
engine speeds, equal to approximately 2.32 volts per
other electrical equipment.
The ammeter should
cell. For example, the voltage regulator setting for 32
indicate some charge into the battery, the amount
cells would be 74 volts and for 56 cells, 130 volts.
depending on the state of charge of the battery. The
charge rate will be higher when the battery is
I. Take all readings at the voltage regulator panel,
discharged, and very little when the battery is charged.
with no loads in the panel circuit except the continuous
loads. The record of this trial setting as found and as
left should be entered on the card in the locomotive.
voltage regulator that should maintain a constant
voltage across the battery throughout the normal range
m. On subsequent inspections, if the specific
of speed and load of the generator.
gravity readings (corrected for temperature and level)
d. An ideal setting of the voltage regulator will
tend to drop off, or consistently remain 15 to 25 points
below the known fully charged specific gravity readings
maintain the specific gravity of the electrolyte at about
of the cells, the voltage regulator has been adjusted at
its fully charged value without using an excessive
too low a setting for the locomotive's working schedule.
amount of water or heating up the battery.
n. To correct this, adjust the voltage regulator from
e. Too high a setting of the voltage regulator will
1/2 to 1 volt higher, and on subsequent routine
result in a water consumption of more than one-half inch
inspections, observe the specific gravity reading
a month and electrolyte temperature exceeding 15
(corrected for temperature and level) of the cell marked
above average outside air temperature.
Excess
by the rotating vent plug in each half of the battery. It
charging, shortens battery life and necessitates more
may be necessary to make more than one such increase
frequent addition of water.
in setting before the specific gravity readings reach the
f. Too low a setting of the voltage regulator will
known fully charged value, with electrolyte temperature
result in specific gravity readings becoming lower from
and water consumption normal. When this condition is
week to week and a water consumption of less than one-
found, from inspection to inspection, the voltage
fourth inch a month. Too little charging may cause a
regulator setting may be considered satisfactory for the
starting failure.
particular working schedule of the locomotive.
g. When a discharged battery is found, and if after
o. If, on routine inspections, specific gravity
checking the voltage regulator, it is found to be properly
readings (corrected for temperature and level), are
adjusted, check carefully for partially loose connections,
found to be at their known fully charged value; with
corroded contact surfaces and frayed or damaged wires.
electrolyte temperature and water consumption higher
Any of these conditions cause high resistance in the
than normal, lower the setting of the regulator in 1/2 to 1
charging circuit. As a result the battery does not receive
volt steps, until normal specific gravity temperature and
its proper charge rate.
water consumption are observed at subsequent routine
h. A standard value cannot be given for setting the
inspections.
voltage regulator, that will cover all service conditions.
p. Make inspection to determine the effectiveness
Proper setting will depend upon the type of equipment,
of a changed setting of the voltage regulator after two or
the working schedule of the diesel locomotive, and
three days of normal operating service.
seasonal temperature changes.
q. Make voltage regulator settings, as found and
i. Before making a voltage regulator setting,
as left, and battery specific gravity readings on battery
check the engine rpm at idling and running speeds, to
card, every time a regulator adjustment is made.
make sure that the engine rpm is within the limits
r. When installing a new regulator with a new
specified by manufacturer.
battery, check the engine rpm.
j. The coils of the voltage regulator must be at
operating temperatures, normally reached after 1 to 2
hours operation. The regulator coils should be hot to the
touch. If the regulator is adjusted while the coils are
cold, the voltage will be different when the coils become
hot.
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