Honda Introduces the EU9i/EU24i/EU28is Series, a New Generation of Compact, Lightweight Generators

June 29, 1998, Japan

Power Products

Tokyo, June 29, 1998 - Honda Motor Co., Ltd., introduced a new generation of three compact, lightweight generators - the EU9i, accompanied by the EU24i and EU28is - in the 2-3 kVA category. The EU24i and EU28is models will be available for sale at all Honda power product dealers nationwide starting June 29, followed by the EU9i on July 21, 1998.
For this EU series, Honda has developed a new high-speed multi-polar alternator. By eliminating the flywheel used until now, this new series is about 50% lighter and more compact than traditional generators of the same output. The EU9i in particular offers dimension and weight characteristics allowing it to be carried with one hand.

This series is also the first in its class to adopt a computer-controlled sine wave inverter. This enables all three generators to precisely control electric frequency and tension variations, making them the perfect source of high quality power for high precision electronic equipment. Unique to Honda, this series also adopts a double encapsulation sound reducing structure to pass the strict "EN", European noise regulations. The eco-throttle (load-dependant speed control-type electronic governor) featured on all three models provides for extremely low noise pollution, improved fuel economy and extended continuous operation capability.

Technical features:

  • Exclusive high-speed multi-polar alternator
    This generator series adopts an exclusive high-speed multi-polar alternator in place of the external multipurpose alternator used in engines until now, locating it in the usual position of the flywheel. The power generator system itself is thus one third lighter than before, allowing for weight and space reduction of close to 50% for the entire generator.
  • Computer-controlled sine wave inverter
    A computer-controlled sine wave inverter was adopted in this class for the first time in the world, allowing for a maximum sine wave distortion rate of 2.5%, for power quality as good as that of commercial power supplies. This makes this generator series the perfect power source for computers, communications, and other measuring-equipment-related uses requiring both stable electric cycle and tension.
  • Double encapsulation sound reduction
    Honda has developed a unique sound-reducing structure for this series. The engine itself is encapsulated to reduce engine noise at the source. A second sound-reducing wall further reduces noise. This double structure helps achieve noise levels between 3 to 9 dB lower than generators of comparable output, making this series compatible with night operation or as a back-up power source for the home.
  • Eco-throttle (load-dependant speed-control-type electronic governor)
    This load-dependent speed-control-type electronic governor automatically controls engine speed to best fit load. This allows for effective engine control when supplying power to equipment requiring large amounts of electric power upon start-up. This translates in not only reduced noise and fuel consumption, but also in extended continuous operation capability. The eco-throttle governor also contributes to reduced exhaust emissions, helping all three models in this series clear the exhaust emission standards set in America by the US Environmental Protection Agency (EPA).

Distinctive features of EU28is/EU24i models:

In the traditional over-100kg-3kVA category, the EU28is and EU24i weigh in at 59 and 54 kg respectively, thus offering a weight reduction of some 50% over the competition. Dimensions are similarly reduced by some 50%. Fuel consumption in the normal range of operation has been reduced by 25 to 30% with noise levels reaching only 49dB(A)/7m (no load) to 58dB(A)/7m (at rated load). These two user-friendly, clean, lightweight, and compact generators are the perfect source for high-quality electric power required by computer and measuring related equipment.

  • These models are powered by well-known Honda GX200/GX160 engines.
  • The two units can be used in parallel (optional parallel operation plug required) to double the maximum electric power supply, thus further extending the range of applications (5.6kVA maximum output using two EU28is units in parallel).
  • The adoption of an electronic governor allows for switching between 50Hz and 60Hz cycles. Power output remains the same no matter which power cycle is chosen.
  • The adoption of an eco-throttle helps further extend continued operation time.
  • Convenience features such as a central control panel, a central maintenance cover and dual electric/recoil starter (EU28is) help make these units extremely easy to use.


Domestic annual sales target for the EU28is/EU24i:

7,500 units


  EU28is EU24i
AC rated output (50/60Hz) 2.8kVA 2.4kVA
DC output 12V-12A 2.4kVA
Continued operation
(25% to 100% rated output)
20 hours to about 7 hours about 25 hours to about 8.1 hours
Fuel tank (l) 12.7
L x W x H (mm) 655 x 445 x 555
Dry weight (kg) 59 54
Noise level (7m)
(25% to 100% rated output)
51* to 58 dB(A)

*Eco-throttle on

EU28is cut views:

  • Inverter unit for high-quality power
  • High-speed multipolar alternator

Distinctive features of the EU9i model:

The EU9i was developed as a versatile, portable unit for many uses in many places. It is powered by the world's smallest and lightest 2.5PS 4-stroke multipurpose engine, the newly developed GXH50, and features both a computer-controlled sine wave inverter (first in its class) and a high-speed multipolar alternator. This EU9i is about 50% lighter than models of comparable output, making it easy to carry and the perfect choice for outdoor purposes. This unit provides as good a power quality as that of a commercial power supply for a safe, reliable mobile power source.

  • It is powered by the GXH50, a newly developed 2.5PS/7,000 rpm 4-stroke multipurpose engine
  • Two units can be used in parallel for a 1.8kVA maximum output to further extend the range of applications.
  • The eco-throttle system, double-encapsulation sound reduction, and large-capacity muffler contribute to a 52 to 57 dB(A) noise level and extended continuous operation capability.
  • The adoption of an electronic governor allows switching between 50Hz and 60Hz cycles. Power output remains the same no matter which power cycle is chosen.
  • Convenience features such as a central control panel, and a central maintenance cover help make this unit extremely easy to use.


Domestic annual sales target for EU9i:

13,000 units


AC rated output (50/60Hz) 900VA
DC output 12V-8A
Continuous operation (25% to 100% rated output) about 8.7 hours to about 3.9 hours
Fuel tank (l) 2.3
L x W x H (mm) 450 x 240 x 380
Dry weight (kg) 13
Noise level (7m) (25% to 100% rated output) 52* to 57dB(A)
  • *Eco-throttle on