8
REV B
60706-232
OPERATING SPEED
The engine-generator must be run at the correct speed in order to
produce the proper electrical voltage and frequency.
CAUTION: EQUIPMENT DAMAGE
The output voltage should be checked to ensure the generator is
working properly prior to connecting a load to the generator. Failure to
do so could result in damage to equipment plugged into the unit and
possible injury to the individual.
All engines have a tendency to slow down when a load is applied.
When the electrical load is connected to the generator, 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 a slightly lower voltage when the generator
is loaded to its full capacity than when running no load. The slight
variation in speed also affects the frequency of the output current.
This frequency variation has no appreciable effect in the operation of
motors, lights, and most appliances. However, electronic equipment
and clocks will be affected if correct RPM is not maintained. See Load
vs. Output chart.
Although individual units and models vary slightly, the normal voltage
and frequency of the engine-generator described in this manual are
approximately as follows, under varying loads:
LOAD vs. OUTPUT
Generator
Load
Speed
(RPM)
Frequency
(Hz)
Voltage
None
3690
61.5
125V
Half
3600
60.0
120V
Full
3510
58.5
115V
The speed of the engine was carefully adjusted at the factory so that
the generator produces the proper voltage and frequency. For normal
usage, the speed setting should not be charged. If the generator is
being run continuously on a very light load, it is often advisable to lower
the operating speed slightly.
Reference “D” in the following image is the speed adjustment for this
engine.
CAUTION: EQUIPMENT DAMAGE
SPEED ADJUSTMENTS SHOULD ONLY BE MADE BY A QUALIFIED
SERVICE TECH.
Whenever making any speed adjustments, check the
unit with a voltmeter and a frequency meter or a tachometer and be
sure the voltage and speed are correct.
Lower voltage may damage both the generator and any load connected
D
to it. Running the engine at excessively high speeds results in high
voltage, which may significantly shorten the life of appliances being
used.
Output voltage should be checked periodically to ensure continued
proper operation of the generating plant and appliances. If the
generator is not equipped with a voltmeter, it can be checked with a
portable meter.
CONNECTING THE LOADS
APPLYING THE LOADS
Allow the engine to warm up for two or three minutes before applying
any load. This will allow the engine to reach normal operating
temperature and oil to circulate throughout the engine. A shot 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.
Receptacles have been provided to allow loads to be connected to the
generator. The loads should be added one at a time. 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.
CAUTION: EQUIPMENT OVERLOAD
Keep the generator load within in the generator and receptacle
nameplate rating. Overloading may cause damage to the generator
and/or the loads.
Most electric tools and appliances will have the voltage and amperage
requirements on their individual nameplates. When in doubt, consult
the manufacturer or a local electrician. The nameplate amperage rating
for electric motors can be misleading. See “Starting Electric Motors” in
the Unit Capabilities.
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 operated with no
load connected. Proper utilization of the receptacles located on the
control panel is necessary to prevent damage to either the receptacles
or the generator. The generator is a limited source of electrical power,
therefore, pay special attention to the receptacle and generator ratings.
The nameplate rating can be obtained through a single receptacle as
long as the receptacles amperage rating is not exceeded.
GROUNDING
All units must be grounded. Drive a 3/4 or 1” copper pipe or rod into
the ground close to the engine-generator set. The pipe must penetrate
moist earth. Connect an approved ground clamp to the pipe. Run a
no. 10 Awg wire from the clamp to the generator ground lug on the
receptacle panel. Do not connect to a water pipe or to a ground used
by a radio system. The engine-generators covered in this manual were
designed primarily for portable use. If you are connecting into a building
wiring system that is already grounded using the 14-60 4 wire plug, you
do not have to ground the unit.
