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Operation
Initial Startup
Generators with Automatic and Manual Voltage Control
1. Disconnect the generator output from the load by opening the
main circuit breaker.
2. Turn the manual voltage adjust rheostat fully counterclockwise.
3. Put the auto-manual switch in the manual position.
4. Start the prime mover, and bring the set to rated speed. Turn the
manual voltage adjust rheostat to reach rated voltage. Close the
output circuit breaker, and apply load in steps until the rated load
is reached. Adjust the manual adjust rheostat as necessary to
obtain the desired output voltage.
5. Gradually reduce load, and adjust the rheostat accordingly until
no load is reached. Open the circuit breaker, and stop the prime
mover.
6. Actuate the auto voltage rheostat. Then start the genset, and
bring it to rated speed. Adjust the voltage to the desired value.
7. Close the output circuit breaker. Then check the generator
voltage and voltage regulation. Apply load in steps until the rated
load is reached.
8. Check for vibration levels at no load and rated load. A slight
increase is normal. As the load is maintained for 2-3 hours, the
vibration levels will gradually increase and reach a final level.
Generators with Automatic Voltage Control Only
Generator has an automatic voltage regulator (AVR) but no
auto-manual switch.
1. Disconnect the generator output from the load by opening the
main circuit breaker.
2. Turn the voltage adjust rheostat fully counterclockwise. Start the
prime mover, and bring the set to rated speed. Turn the voltage
adjust rheostat to obtain the desired voltage.
3. Close the output circuit breaker, and apply load in gradual steps
until the rated load is reached. Note the voltage regulation with
the changes in load steps.
4. Check for vibration levels at no load and rated load. A slight
increase is normal. As the load is maintained for 2-3 hours, the
vibration levels will gradually increase and reach a final level.
Restore Residual Magnetism (Field Flashing)
The direct current necessary to magnetize the revolving field is
obtained from the exciter. Upon starting the generator, current and
voltage is induced into the exciter by the magnetic lines of force set up
by residual magnetism of the exciter field poles. Residual magnetism
of the exciter field poles may be lost or weakened by a momentary
reversal of the field connection, a strong neutralizing magnetic field
from any source, or non-operation for a long time. If the generator
fails to generate voltage after it has come up to rated speed, it may be
necessary to restore residual magnetism. See Figure 15.
CAUTION:
Do not make
connections or otherwise make contact
with the generator leads or other devices
connected to them unless the genset
is stopped and the phase leads are
grounded.
CAUTION:
Do not actuate the
auto-manual switch with full load applied
to the generator. Whenever possible, stop
the generator before starting.
CAUTION:
Refer to the voltage
regulator manual for complete details
and possible additional instructions.
Damage to the rotating diodes, generator,
and voltage regulator can be caused if
the regulator is operated improperly.
CAUTION:
Operating the unit
beyond nameplate values may cause
equipment damage or failure.
NOTE:
If the polarity of the exciter is
reversed by flashing the field, it may be
corrected by interchanging the battery
leads.
Summary of Contents for 4P10
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