Zoom on the Yamaha EF1000iS
In a nutshell, the Yamaha EF1000iS is a quiet, compact and lightweight portable inverter generator mostly geared towards:
- Camping and tailgating buffs looking to enhance their experience
- DIYers who wish to improve their efficiency with tools
The following sections will present you in detail its power characteristics, the different outlets it offers, its overall portability, the extra features it benefits from, and any relevant emission compliance details.
Power & Run Time
The Yamaha EF1000iS's design includes a gasoline-fueled 50 cc Yamaha MZ50 OHV 4-stroke engine. With a 120V output, it gives a running wattage of 900W and also a peak wattage of 1000W.
Enjoying a really low noise rating of 47 dBA (less noisy than bird calls) which secured it a place in our list of the 10 quietest portable generators, the inverter generator is started via a simple traditional pull-start mechanism.
This generator features Yamaha's Smart Throttle™. This load-sensing feature automatically adjusts engine speed to match its load in order to offer greater fuel efficiency and noise reduction.
The EF1000iS can operate for up to 11.9 hours with a full tank (fuel consumption around 0.06 GPH), due to its fuel capacity of 0.66 gallon.
Sensitive electronics can be safely plugged in the AC outlets, as the EF1000iS produces a clean sine wave, with a <2.5% Total Harmonic Disruption (THD).
The control panel provides the upcoming 2 AC outlets:
In addition, it provides 1 DC outlet: there's a 12V 8A receptacle with which charging your batteries is made easy.
Thanks to its closed inverter generator design (L17.7 x W9.4 x H14.9 in), the Yamaha EF1000iS, is more esthetical than a typical, open frame generator. This type of design is the most modern and convenient way to recreationally generate power.
Weighing just 27.9 lbs, the EF1000iS can be considered a lightweight portable generator. The product’s power can be enjoyed on-the-go, as it can be moved by a single person without trouble. Further convenience is provided by its handle (molded in the case), as it allows you to carry it effortlessly.
Good to know: This unit ranks 5th in our list of the 10 smallest portable generators.
Some light indicators allow you to instantly see if the generator is overloaded, the oil level is too low and the generator is ready.
Security-wise, this product benefits from an automatic low oil shut-off (Oil Watch system) and an overload protection (circuit breaker), which gives you a complete peace of mind when using it.
Yamaha's Oil Watch warning system gives you an extra peace of mind. This feature enhances long-term durability by preventing engine damage and costly repairs. Once the oil begins to run low, the generator automatically shuts off and cannot be re-started until oil is added.
As for its accessories, apart from the previously mentioned features, the Yamaha EF1000iS also comes with the basic documentation and an owner's manual (opens in a new tab), allowing you to start it right away.
The Yamaha EF1000iS is EPA-approved and CARB-compliant. Thus, selling and purchasing this generator is allowed in each of the 50 states, including California.
Moreover, it features a spark arrestor and therefore, can be used in forested areas.
The Yamaha EF1000iS versus other generators
The following charts are provided to give you an idea of how some of the key specs of the Yamaha EF1000iS compare to generators of similar power (between 500 and 1500 W).
- Weight-wise, the Yamaha EF1000iS has only 27.9 lbs, which renders it one of the lighter generators which produce 500 to 1500 rated watts. If weight matters to you, one of the champions in this power range is the Sportsman GEN1000i with only 20.3 pounds.
- With a lowest noise rating of 47 dBA, the inverter generator is one of the more quiet of the generators of similar power. If noise emissions are one of your priorities, you may be interested in the Honda EU1000i, one of the least noisy generators similarly powerful as this one, rated for 42 dBA.
- Since the EF1000iS boasts with a run time of up to 11.9 hours at 25% load, it can be safely judged as a device of a higher run time than most generators of a comparable output. If you consider autonomy on a single full tank as one of the deciding factors, one of the generators in the same power range that offers the highest run time is the Powermate PM2000, with up to 14 hours.
- The run time is important, but also hugely depends on the capacity of the fuel tank and doesn't mean much if we don't talk about fuel consumption as well. This inverter generator is one of the most fuel efficient models of the aforementioned output range, as its estimated fuel consumption reaches just 0.06 GPH (gallon per hour) at 25% load.
As you can see from this interactive chart, when compared to other 500-1500W generators, the Yamaha EF1000iS is on the expensive side of the price range.
While certainly not the cheapest of its kind, purchasing it would most likely also mean enjoying the reliability of a high-end product.
The bottom line
- Lightweight (27.9 lbs)
- Quiet for its power (47 dBA)
- High run time
- Fuel efficient
- On the expensive side
- No data center
- No electric start
- No parallel ports
Features and Specifications
|Engine||50 cc Yamaha MZ50 OHV 4-stroke|
|Voltage||AC: 120V 60 Hz, DC: 12V|
|Running watts||900 W|
|Starting watts||1000 W|
|Running amps||7.5 amps|
|Peaks amps||8.3 amps|
|Run time @50% load||Unknown|
|Run time @25% load||11.9 h|
|Automatic Voltage Regulation||Inverter|
|AC outlets||1x Duplex 120V 15A (5-15R)|
|DC outlets||1x 12V 8A receptacle|
|Indicators||Low oil, overload and output ready|
|Fuel tank||0.66 gal|
|Approx. dimensions (L x W x H)||17.7 x 9.4 x 14.9 in|
|Noise (lower limit)||47 dBA|
|Security||Low oil and overload protection|
Unlike many websites, we did our best to research each of the specs above. That being said, we are not immune to making the occasional mistake or omission. Should you notice any missing or incorrect values, don't hesitate to suggest improvements so we can address the issue.
With a rich history of over 130 years, the Japanese based Yamaha Corporation, founded in 1887, has tipped its fingers in every industry imaginable, most notably motorcycles, musical instruments and electronics. The company boasts with a wide range of products, including many of the top rated portable generators. However, it has been reported that many of the newer models are made in China, rather than Japan.
The Yamaha EF1000iS is covered under a warranty for up to 3 years. This warranty may be limited and may not cover all parts of the generator.
For more information about the warranty of Yamaha generators, please consult Yamaha's warranty policies (opens in a new tab). Alternatively, you can also contact their Customer Support: 1-800-962-7926.
Questions & Answers
What can it power?
|Item||Running Watts||Starting Watts|
|At home||Rice cooker||650||650|
|Set of 5 LED light bulbs||55||55|
|Total||705 W||705 W|
|For camping||RV refrigerator||180||600|
|Pair of small speakers||45||45|
|Total||575 W||995 W|
|For work||Paint sprayer||600||600|
|Total||680 W||680 W|
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