Honda eu2000 generator output waveform

Hello all,
I hooked up an o-scope to my Honda EU2000 generator and discovered
something interesting about the waveform. Initially the waveform
looked like a regular 60 HZ sine wave. When I changed the range to
10V/CM I saw that the 60 HZ waveform is actually a 10 volt peak to
peak 20 KHZ waveform varying at 60 HZ.
I guess this is a result of how the unit forms its output.
I decided to hook up the scope when I couldn't get a stable frequency
reading with a Fluke 87.
Regards,
Morgan Ford
Reply to
Morgan
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What do you mean by not stable? Less than 1 hz would be no big deal, in my opinion Are you testing with a load? If not put something like 50% on it and try again. Set the hertz with 50% load and then check it.
Reply to
SQLit
Er, that's called "carrier."
[From the inverter...try loading it with a 100-watt incandescent lamp and see if it looks any better.]
--s falke
Reply to
s falke
By not stable, I mean it was jumping between 60 HZ and several KHZ. Sometimes the fluke locked in on the 60 HZ and sometimes it tried to read the 20 KHZ. Adding a 500 watt load didn't change either the Fluke's behavior or the scope presentation.
Has anyone else out there hooked up a scope to an EU2000?
Reply to
Morgan
Sounds like it's using PWM to form the sine wave, pretty much the best way of doing it these days, gives a nice clean sine wave (if done right) and is very efficient. TTYL
Reply to
repatch
This is pretty interesting.
Is it actually more efficient to generate DC and then use an inverter to turn that into AC? I'm having a hard time believing this to be the case.
Why do they do this? Most generators I've seen just spin at 1800RPM or so and derive AC directly using a true alternator.
-Z
Morgan wrote:
Reply to
Zorin the Lynx
Some new Honda & Yamaha generators actually produce high-frequency (several hundred Hz) and 3-phase AC output and convert it to something like 200VDC first, then they use an inverter to produce the 120VAC, 60Hz sinewave output. If the 200VDC is not well filtered, then you could see ripples (or sawtooth like waveform) at several thousand Hz riding on top of the sinewave.
They are more expensive (over $1000 for 3000 watt generator), but they can power computers, TV & other solid-state electronic loads far better than some cheap generators whose output waveform looks like a teenager's spiky hairdo (which will cause overheating of solid state devices & damage TV's, computers, etc.).
If someone wants to power TV, computer & other electronic appliances with engine generator, always verify that the output waveform is a regulated & clean sinewave (i.e., computer-grade sinewave). Noisy generator outputs can still power lights, refrigerators & heaters (in other words, motors & resistor loads are OK), but one should never power electronic loads (i.e., TV, computer, etc.)
Reply to
Nam Paik
What???Are you joking???The waveform coming from any inverter is not sinusoidial, but square AND is destructible for most appliances, except incadescent lights.
-- Dimitris Tzortzakakis,Greece
Ï Zorin the Lynx Ýãñáøå óôï ìÞíõìá óõæÞôçóçò: bs8j6t$rt$ snipped-for-privacy@ottoman.cs.fiu.edu...
Reply to
Tzortzakakis Dimitrios
"Tzortzakakis Dimitrios" wrote in message news:bsfh12$jp3$ snipped-for-privacy@usenet.otenet.gr...
You need to study modern inverter technology some more before you post anything else. We test many inverter based generators and many produce nearly perfect (less than 5% thd) sinusoidal waveforms. Cheaper inverters do not. The square wave will not hurt electronic loads. Square wave output can be troublesome for inductive loads, particularly motors.
Charles Perry P.E.
Reply to
Charles Perry
I too am impressed with the waveform produced by some of the newer generators. I scoped the output of one model from Honda, and Yamaha, both loaded, and unloaded. A fellow had asked me to determine if he could safely run a computer from them. After looking at the waveform of both, I explained to him that it was in some ways more suitable than that supplied where the computers were currently located.
Is anyone aware of this type of inverter technology available as a stand alone unit without a generator?
Thank you.
Louis
Reply to
Louis Bybee
Maybe batteries could be connected to the inverter input. This would allow the generator to be turned off for refueling without losing output.
Morgan Ford
Reply to
Morgan
X-No-Archive: Yes
Zor> This is pretty interesting.
So the engine speed can be varied according to load to reduce fuel consumption and noise as well as having a better frequency stability as the frequency is set by the inverter.
A true alternator generator's frequency is a direct function of rotor speed and the rotor must turn at 3600 or 1800 RPM regardless of load. A generator running at 3600RPM is pretty load.
Reply to
AC/DCdude17
True, 3600 and 1800 RPM are possible speeds, but not the only ones. I worked for several years with a 600 RPM diesel-gen set. And of course, water turbine systems often run at slower speeds. Even many modern EMD diesel-gen sets only run 900 RPM. The slower speed diesels last 'forever'.
daestrom
Reply to
daestrom
Hello, all. We have two Honda EU2000I generator-inverters that were purchased two years ago for field use. They are lightweight, very quiet and have proven very reliable (as is typical of Honda products). My question is does anyone know what is the frequency-determining element in the inverter section? Crystal? R-C time constant? I am curious how the Honda engineers designed the inverter to provide a nominal 60 Hz output over a wide operating temperature range. It can get quite warm inside the generator enclosure. Thanks for your time and comment. Sincerely,
John Wood (Code 5550) e-mail: snipped-for-privacy@itd.nrl.navy.mil Naval Research Laboratory 4555 Overlook Avenue, SW Washington, DC 20375-5337
Reply to
J. B. Wood
You mean "true sine wave" inverters? They existed years before the "inverter generators" came on the market. They are expensive.
%mod%
Reply to
modervador
A similar Honda generator EB3000i that we looked at a couple of years ago had used AC to DC converter to change high frequency (and 3-phase)raw AC output of the generator. The high voltage DC (around 200 to 400VDC, I think) was fed into an electronic module (inverter module) which was filled with epoxy for protection against moisture & vibration (also prevents reverse-engineering), so we could not really see what circuit was used to get the precise 120VAC, 60Hz sinewave inverter output. But that type of circuit is typically powered by a small microcontroller with sinewave generating pulse-width-modulated converter (all sinewave UPS and inverters use similar design circuit nowadays). I thought it was a very good way to produce clean sinewave at stable voltage & frequency. I don't know if the EU2000I (I am guessing that their suffix I stands for Inverter - does anyone know for sure?) uses the same kind of AC to DC & DC back to AC topology. If Honda engineers can get reply, it would be super.
Reply to
Nam Paik
That souns like you are about to worship inverters, like has happened with DVDs.'Before I post anything else'? I studied that technology when I did my graduation study, it was about generation-transmission-distribution.The wind-generators can't produce ALL the electricity in a system, because they produce too much harmonics (not even more than 10%).
-- Dimitris Tzortzakakis,Greece Visit our website-now with aircondition!
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Ï Louis Bybee Ýãñáøå óôï ìÞíõìá óõæÞôçóçò: zsMGb.656257$Tr4.1662686@attbi_s03...
Reply to
Tzortzakakis Dimitrios

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