Yamaha EF4500iSE Theory & Diagnostics Manual page 11

Page 5
Continuous Running Time
EF3000iSE is able to run for 20.5 hours with 1/4
load with fuel tank full, when economy control switch
is on.
With rated load: 8.0 hours
With 1/4 load: 20.5 Hours
Refer to Section 3 for model specific run times and
rated load information.
Frequency Variation
Conventional synchronous generators have an
engine speed with no load set at approximately 6%
higher than rated engine speed (3600rpm for 60 Hz)
to maintain rated frequency when full rated load is
applied. This is the reason why no-load frequency is
slightly higher than rated frequency.
However, adapting an inverter system, which gener-
ates genuine sine wave electricity, the frequency
variation of an inverter generator is not influenced by
the engine speed. Therefore, an inverter generator
provides constant AC output frequency even if the
load changes which is equivalent quality to the com-
mercial power supplies.
Generator Information and Theory
The frequency variation of Yamaha inverter gen-
erators is less than 0 .1% .
Voltage Variation
The output voltage with no load is approximately
10% higher than rated voltage for a case of conven-
tional synchronous type generators to achieve the
rated voltage when full rated load is connected. Thus
the voltage variation occurs due to the change in
engine speed and the influence of the internal resis-
tance.
However, adapting an inverter system, the voltage
variation can be minimized, because the output volt-
age cannot be influenced directly from engine
speed.
The voltage variation of Yamaha inverter genera-
tors is smaller than 3% .
The waveform distortion rate of Yamaha inverter
generators is smaller than 2 .5% .
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