BASIC
0
PERATI0
N
(continued)
OPERATINGSPEED
-
The engine-generatormust be run
?t the correct speed inorderto producethe properelec-
,
.rical voltage and frequency.
The output voltage should be checked
A
to insurethe generator isworking prop-
erly prior to connecting a load to the
generator. Failuretodo so could result
in damage to equipment plugged into
the unit and possible injury to the indi-
vidual.
1.
All engines have a tendency to slow down when a
load is applied.The governoron the engine isdesigned
to holdthe speed nearly constant.When the electrical
load connected to the generator is increased, the
engine is more heavily loaded, and as a result the
speed drops slightly. This slight decrease in speed,
together with the voltage drop within the generator
itself, results in aslightly lowervoltage when the gen-
erator is loaded to its full capacity than when run-
ning no load.The slight variation inspeed also affects
the frequency of the output current. This frequency
variation has no appreciableeffect inthe operation of
motors, lights and most appliances. However, elec-
tronic equipment and clocks will be affected ifcorrect
RPM is not maintained. See load vs. Output chart.
Although individual units and models may vary
slightly, the normal voltage and frequency of the
engine-generatorsdescribed inthis book are approx-
-
imately as follows, under varying loads:
LOAD vs. OUTPUT
Generator Frequency Generator voltage
Load Speed (Hz)
120V 240V
Amlied* (RPM) Rec~t. Rec~t.
None
3690 61.5 129V 258V
Half
3600 60.0 120V 240V
Full
3510
58.5
115V 230V
*Portion of plant's rated output current.
2.
The speed of the engine was carefully adjusted at
the factory so that the generator producesthe prop-
er voltage and frequency. For normal usage, the
speed setting should not be changed. If the generator
is being run continuously on a very light load, it is
often advisable to lower the operating speed slight-
ly. Whenever making any speed adjustments check
the unit with a voltmeter or tachometer and be sure
the speed is neither too high nor too low.
Unlessthe engine isequipped with the automatic
conserver assembly the engine must be run at the
specified speed at all times. Lowervoltagemay dam-
age both the generator and any load connecting to
it. Running the engine at excessively high speeds
results in high voltage, which may significantly
shorten the life of appliances being used.
3.
Output voltage should be checked periodically to
ensure continued proper operation of the gener-
ating plant and appliances. If the generator is not
equippedwith a voltmeter, it can be checked with
a portable meter. Frequencycan be checked by us-
ing an electric clock with a sweep second hand.
Timed against a wrist watch or a stop watch the
clock should be correct within
+
1
-
2
seconds.
CONNECTING
THE
LOADS
1
.ApplyingThe Load
-
Allow theengine towarm up for
two or three minutes before applying any load. This
will allow the engine to reach normaloperatingtemp-
erature and oil to circulate throughout the engine.A
short warm-up time will permit the engine to work
more efficiently when the load is applied and will
reduce the wear in the engine, extending its life.
A. Receptacles have been provided on the control
panel to connect the loads to. The loads should
be applied gradually. If a large motor is being
started or multiple motors are being started, they
should be started individually and the largest
should be started first.
I]
erator and receptaclenameplaterating.
Overloading may cause damageto the
B.
Most electric tools and appliances will have the
voltage and amperage requirements on their in-
dividual nameplates. When in doubt consult the
manufactureror a local electrician.The nameplate
amperage rating for electric motors can be mis-
leading,see Starting Electric Motors insection
B.
C. These engine generator sets are inherently self
regulating based on engine speed. The engine
governor will automatically adjust itself to the
load. No harm to the generator will result if it is
run with no load connected.
D. Proper utilization of the receptacleslocatedon the
control panel is necessary to prevent damage to
either the receptacles or the generator. The gen-
erator is a limited source of electrical power,there-
fore pay special attention to the receptacle and
generator ratings.The nameplate ratingcan be ob-
tained through a combination of receptacles or a
single receptacle as long as the receptacle amp-
erage rating is notexceeded. Boththe
120
and
240
volt receptacles can be utilized at the same time.
See section
B
for proper load separation.
2.
Grounding
-
All units must be grounded.
A. Drivea
314
or
1"
copper pipeor rod into the ground
close to the engine-generatorset. The pipe must
penetrate moist earth. Connect an approved
ground clamp, to the pipe. Run a no.
10
Awg wire
from clamp to the generatorground lugor the bat-
tery negative terminal. Do not connect to a water
pipe or to a ground used by a radio system.
