generator mufflers

"john smith" wrote in message
...
In article
,
"Vaughn Simon" wrote:

If you really want quiet, those inverter generators made by Yamaha and
Honda are awesome. Expensive, but after all this is an aviation group.
Money is obviously no object, right?

Vaughn, I am having difficulty finding a Yamaha generator dealer locally.
Yamaha's site is no help.
Is this something that is a regional commodity?

I recently bought two Yamaha generators for my employer from these people:
http://www.yamahagenerators.com/ and got excellent service. I agree that it
would be better to support a local dealer even if you pay a bit more, but my
search was as fruitless as yours. Even our local Honda dealer does not seem to
stock generators with any consistency, even though I live in a hurricane area.

Vaughn

"john smith" wrote in message
...

Vaughn, I am having difficulty finding a Yamaha generator dealer locally.
Yamaha's site is no help.
Is this something that is a regional commodity?

John...........

After owning two Yamaha generators and one Yamaha Virago motorcycle, I can
say that starting the motors of all three is a continual problem. Neither of
the generators would fire without removing the spark plug and priming the
cylinder directly.

The motorcycle is an well-known abomination in the starting department.
Google "Virago starter" for 69,500 hits on how to fix the problems. Even
after these were well-known by Yamaha, they continued to manufacture this
joke of a starter for years. I would never buy another product from this
company.

I have had a Honda 5000 watt 120/240 volt generator for 7 or 8 years now.
Besides an occasional oil change it has required zero maintenance during
this time. It almost always starts on the first pull. Even if I am trying to
slowly pull it through to get some gas in the system it will start, scaring
the heck out of me. I give it my unqualified recommendation.

FWIW,
Rich S.

"Rich S." wrote

After owning two Yamaha generators and one Yamaha Virago motorcycle, I can
say that starting the motors of all three is a continual problem. Neither
of
the generators would fire without removing the spark plug and priming the
cylinder directly.

That does truely suck. Too bad they can't get that fixed, because my 75
Yamaha bike was a good one.

I have had a Honda 5000 watt 120/240 volt generator for 7 or 8 years now.
Besides an occasional oil change it has required zero maintenance during
this time.

My dad has had a Honda generator for almost 20 years, and it sometimes goes
2 or 3 years without being started. Even though it has not had any gas
treatment or any other special car, it starts within the first 2 or 3 pulls.
They are amazing, for their legendary easy starting.

The Honda generators are quite quiet, but they are nothing like the Yamaha.
As far as I could tell, nobody else makes one in the small to medium size
that is even half as quite. If Yamaha can do it, the others could, too.
They need to get with it!

So I guess you pick your poison. Quiet and hard to start, or easy to start
and loud.
--
Jim in NC

"Morgans" wrote in message
...
The Honda generators are quite quiet, but they are nothing like the Yamaha.

I have not compared the exact specks, but both the Yamaha and Honda
inverter generators are very competitive and comparable, each manuvering for a
tiny marketing advantage on the other. I have a Honda EU2000i, and it is very
quiet. We have two 1000 watt Yamaha inverter generators at my shop and they are
also very quiet (and easy to start). Honda and Yamaha are to the generator
world what Honda and Toyota are to the auto world, you won't go far wrong with
either one.

Vaughn

"Vaughn Simon" wrote in message
...

"Morgans" wrote in message
...
The Honda generators are quite quiet, but they are nothing like the
Yamaha.

I have not compared the exact specks, but both the Yamaha and Honda
inverter generators are very competitive and comparable, each manuvering
for a
tiny marketing advantage on the other. I have a Honda EU2000i, and it is
very
quiet. We have two 1000 watt Yamaha inverter generators at my shop and
they are
also very quiet (and easy to start). Honda and Yamaha are to the
generator
world what Honda and Toyota are to the auto world, you won't go far wrong
with
either one.

Glad to hear that the Yamaha generator is east to start.

What is it about the inverter generators that makes them so quiet? Do they
run less RPM, or what is it? I have never been around one.

I am hesitant about an inverter, being the final drive. I had a 1500 watt
inverter that would not run the smallest 110 air conditioner that I could
find, even though it was rated as an efficient AC, and the amps rating
should have made it well under the rated output of the inverter. In fact,
the inverter was almost two times as big as what it should have needed to
be, according to it's rated output. I even put extra cooling fans to it,
and still, it would kick out with a thermal overload after about 5 or 10
minutes.

I also burnt out a power tool battery charger, even though I knew I was
taking a risk, according to the inverter manual. Most inverters have a
square wave output, instead of a sine wave output, and that will kill
chargers that run at a high voltage potential, until the load is attached to
the charger. So I am skeptical of inverters, unless it is sine wave output,
and the Yamaha inverter generator, looks to me, to be a square wave AC
output.

Anyone know what the waveform of these units are?
--
Jim in NC

"Morgans" wrote in message
...


Glad to hear that the Yamaha generator is east to start.

What is it about the inverter generators that makes them so quiet? Do they
run less RPM, or what is it? I have never been around one.

Yes, they actually make DC and then feed it to the inverter. A normal
generator runs at 3600 RPM all the time. An inverter generator's engine only
makes enough RPM to make exactly the power needed to keep the inverter happy.
The less load, the fewer RPMs. You also save a bunch of gas since the engine is
not always revving its little heart out. Those little Yamaha 1000-watt
generators will run a refrigerator for about 12 hours on a single gallon of
gasoline.

I am hesitant about an inverter, being the final drive. I had a 1500 watt
inverter that would not run the smallest 110 air conditioner that I could
find, even though it was rated as an efficient AC, and the amps rating
should have made it well under the rated output of the inverter. In fact,
the inverter was almost two times as big as what it should have needed to
be, according to it's rated output. I even put extra cooling fans to it,
and still, it would kick out with a thermal overload after about 5 or 10
minutes.

It was a "Modified Sine Wave" inverter right? That is a big difference!
Refrigeration motors tend to start hard and run hot when ran with square wave
power. All inverter generators that I have seen so far use a true sine wave. I
have tried those little 1000-watt Yamahas on two different refrigerators with
excellent results. My 2000-watt Honda inverter generator barely notices my big
side-by-side refrigerator, but I have not yet tried it on an air conditioner.

Also, consumer refrigeration units tend to require a very large startup
surge compared to their "normal" running load. There are modifications you can
make to reduce that surge significantly.


Anyone know what the waveform of these units are?

Like I said, all that I have seen so far are sine wave.

Vaughn



--
Jim in NC

Vaughn Simon wrote:
"Morgans" wrote in message
...
The Honda generators are quite quiet, but they are nothing like the
Yamaha.

I have not compared the exact specks, but both the Yamaha and Honda
inverter generators are very competitive and comparable, each
manuvering for a tiny marketing advantage on the other. I have a
Honda EU2000i, and it is very quiet. We have two 1000 watt Yamaha
inverter generators at my shop and they are also very quiet (and easy
to start). Honda and Yamaha are to the generator world what Honda
and Toyota are to the auto world, you won't go far wrong with either
one.

Pardon my ignorance, but what is an "invertor generator"?


AP

"Alan Petrillo" wrote

Pardon my ignorance, but what is an "invertor generator"?

Most generators set the 60 cycles per second AC (alternating current, like
your house) power, by running the engine at a governed RPM. It is
different, depending on the brand, and how many different windings the
generator head has, but many times the engine runs at 3,600 RPM. They run
that speed, if you are powering a light bulb, or a big welder - same RPM,
wildly different loads.

An inverter generator has what is close to an automobile alternator, but
usually much bigger, and possibly different voltage. It puts out DC (Direct
current, like your car) power, but not what your appliances can use.

Added on to the DC output is a power inverter, which makes the voltage
change to AC, at an electronically controlled 60 cycles per second. If you
are running nothing, or a small load, the engine only is at idle, and making
enough electricity for a small load.

As you put larger loads on it, the inverter senses that it needs more power
for the big load, and brings the RPM up higher on the engine, so it is
making more HP, and sending more power to the inverter. It constantly
changes the RPM, making only what HP is needed to carry the load.

Some inverter generators even have a battery added in the generator, so when
you have a high surge load, like starting a motor or air conditioner
compressor, the battery takes care of sending the extra power for a few
seconds, until the starting load of the appliance is done. The end result
is a unit that has a more steady RPM of the motor, and it will be able to
run a larger motor or AC, because it has an extra weapon to use to take care
of the starting surge, rather than adding a larger engine.
\
That is the difference between the two Yamaha inverter generators that are
both 3,000 watt, but a couple hundred different in price, if you read the
fine print in the specifications.

I hope that is enough explanation, but not too much. It was a long one,
huh? g
--
Jim in NC

Jim, too bad you can't hear my applause. That was such a good
explination, I even understood it. Thanks
Lou

Sine wave, square wave and things inbetween.
It's all about the "area under the curve".
Tim "The Tool Man" Taylor always wanted "more power".
Sometimes, this is not a good thing.
The "power" delivered by cycle, be it square wave, sine wave or things
inbetween, can be found by calculating the area under the curve.
For a square wave, it is simple the width times the height.
A sine wave takes a little more math, but can be approximated by the
area under half a circle ((1/2)*pi*(r**2)).
These are greatly simplified for demonstration purposes.
Drawing a sign wave inside the square wave visually illustrates that
there is more power delivered by the square wave than by the sign wave.
This is why some devices heat up. They cannot handle the extra power
delivered by the square wave.
There are methods to reduce the area above the sign wave within the
square wave, but they complicate the inverter design and can add volume
to the packaging.
Pulsewidth modulation, an electronic means of making different length
square waves is an elegant solution, but adds cost and complexity.
Capacitor banks to build a stepped sign wave are more simple and less
costly but very bulky. The more steps desired to closer approximate the
sign wave, the more capacitors are required.
Like airplanes, power supplies are tradeoffs.