Small Solar Chargers

Frank Bemelman wrote:

"Spehro Pefhany" schreef in bericht On Sun, 18 Dec 2005 00:33:33 +1100, the renowned George Ghio

When people try to sell a "Modified Sine wave" inverter they are either ignorant or shysters.
To paraphrase a classic George Carlin routine- "I'll tell you what 'modified sine wave' means-- no f*cking sine waves".
I would label the boxes with a nice star shaped sticker "powerful harmonic sine waves".

ha, youre a natural :)
NT

On Sun, 18 Dec 2005 14:05:32 +1100, George Ghio wrote:

I have nothing against the modified sq. wave inverters.
Misrepresenting a product is lying.

Using industry-accepted terminology to describe a product does not constitute lying.

Nope, shysters or ignorant. The ignorant don't know any better and the shyster is a lier and a thief. No point doing business with either of them.

No point in doing business with the ignorant? Sounds like a good idea considering the following Ghioism....

"Modified Sq. Wave" is just that. Sine Wave is not stepped.

<sigh> You might correct your error by listing some popular "sine" wave inverters, and the number of steps in their "not stepped" waveforms.
Wayne

wmbjk wrote:

On Sun, 18 Dec 2005 14:05:32 +1100, George Ghio <AKA@nomailhere.com wrote:
I have nothing against the modified sq. wave inverters.
Misrepresenting a product is lying.
Using industry-accepted terminology to describe a product does not constitute lying.

When a lie becomes industry-accepted terminology then the industry is in deep shit.

Nope, shysters or ignorant. The ignorant don't know any better and the shyster is a lier and a thief. No point doing business with either of them.
No point in doing business with the ignorant? Sounds like a good idea considering the following Ghioism....
"Modified Sq. Wave" is just that. Sine Wave is not stepped.
sigh> You might correct your error by listing some popular "sine" wave inverters, and the number of steps in their "not stepped" waveforms.

Yes Mildred there really are true sine wave inverters that are not just a sq. wave with many, many steps.
Do your own fucking search.

Wayne

On Mon, 19 Dec 2005 16:35:16 +1100, George Ghio wrote:

wmbjk wrote: On Sun, 18 Dec 2005 14:05:32 +1100, George Ghio <AKA@nomailhere.com wrote:
When a lie becomes industry-accepted terminology then the industry is in deep shit.

It was never a "lie" except in your ignorant vernacular. And for an industry in "deep shit" it seems to be doing rather well overall.

"Modified Sq. Wave" is just that. Sine Wave is not stepped.
sigh> You might correct your error by listing some popular "sine" wave inverters, and the number of steps in their "not stepped" waveforms.
Yes Mildred there really are true sine wave inverters that are not just a sq. wave with many, many steps.

Another unsupported claim by Mr. Hole Digger. But at least you've admitted in weasel-speak that some <snorf> "sine" wave inverters *do* have stepped waveforms. Would you say that they're manufactured and sold by liars?

Do your own fucking search.

I take that to mean that you won't be providing any examples of sine wave inverters with stepless waveforms. What a shocker.
Wayne

On Mon, 19 Dec 2005 10:04:21 -0500, Steve Spence wrote:

wmbjk wrote: On Mon, 19 Dec 2005 16:35:16 +1100, George Ghio <AKA@nomailhere.com wrote:
wmbjk wrote:
On Sun, 18 Dec 2005 14:05:32 +1100, George Ghio <AKA@nomailhere.com wrote:
When a lie becomes industry-accepted terminology then the industry is in deep shit.
It was never a "lie" except in your ignorant vernacular. And for an industry in "deep shit" it seems to be doing rather well overall.
"Modified Sq. Wave" is just that. Sine Wave is not stepped.
sigh> You might correct your error by listing some popular "sine" wave inverters, and the number of steps in their "not stepped" waveforms.
Yes Mildred there really are true sine wave inverters that are not just a sq. wave with many, many steps.
Another unsupported claim by Mr. Hole Digger. But at least you've admitted in weasel-speak that some <snorf> "sine" wave inverters *do* have stepped waveforms. Would you say that they're manufactured and sold by liars?
Do your own fucking search.
I take that to mean that you won't be providing any examples of sine wave inverters with stepless waveforms. What a shocker.
Wayne
although I find myself in agreement with george (very scary, especially after his recent voltage driven LED faux pas) that the moniker "Modified Sine Wave" is a misleading term, and should be changed to "Modified Square Wave" in order to more accurately reflect the technology,

If only he'd stopped at making that point. But Judge Ghio had to pontificate about liars, ignorance, and shysters. He just never knows when to shut up. Anyway, the term is unlikely to ever be changed, and it's a pretty minor issue IMO.

you seemed to have gotten under his skin a bit. Congrats.

It's sooooo easy, since he *always* defends his mistakes with more mistakes. The topper was "never wrong mate". Now *that's* funny. Apparently the weasel definition of "never" is "most of the time".
Wayne

On Mon, 19 Dec 2005 16:30:20 +0000 (UTC), dold@XReXXWindX.usenet.us.com wrote:

the moniker "Modified Sine Wave" is a misleading term, and should be changed to "Modified Square Wave"
I would prefer "stepped sine wave". But I can accept the term "modified sine wave" as marketing speak that has been on lots of UPS boxes for 20 years. (UPS itself being inaccurate for a standby power source.)

A chirped-frequency, nanosecond-wide, random-amplitude pulse train is a modified sine wave.
John

the moniker "Modified Sine Wave" is a misleading term, and should be changed to "Modified Square Wave"

I would prefer "stepped sine wave". But I can accept the term "modified sine wave" as marketing speak that has been on lots of UPS boxes for 20 years. (UPS itself being inaccurate for a standby power source.)
-- --- Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8,-122.5

Plonk!
Jim

"George Ghio" wrote in message

Do your own fucking search.

On Mon, 19 Dec 2005 08:51:30 -0800, John Larkin wrote:

dold@XReXXWindX.usenet.us.com wrote:
the moniker "Modified Sine Wave" is a misleading term, and should be changed to "Modified Square Wave"
I would prefer "stepped sine wave". But I can accept the term "modified sine wave" as marketing speak that has been on lots of UPS boxes for 20 years. (UPS itself being inaccurate for a standby power source.)
A chirped-frequency, nanosecond-wide, random-amplitude pulse train is a modified sine wave.
John

;-)
Thanks! Rich

In alt.solar.photovoltaic John Larkin wrote:

A chirped-frequency, nanosecond-wide, random-amplitude pulse train is a modified sine wave.

I will accept that definition as offered. Does that preclude having any other valid definitions?
-- --- Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8,-122.5

Steve - How many equal "steps" are necessary for the MSW inverter to be a sufficiently close approximation to a "rotary" sine wave?

wmbjk wrote:

I take that to mean that you won't be providing any examples of sine wave inverters with stepless waveforms. What a shocker.
Wayne

Take it to mean that you can't prove that true sine wave inverters don't exist.
Modified Square Wave inverters = True
Modified Sine Wave inverters = False

On Mon, 19 Dec 2005 23:51:48 -0800, philkryder wrote:

Steve - How many equal "steps" are necessary for the MSW inverter to be a sufficiently close approximation to a "rotary" sine wave?

It depends how you count "steps". I once worked with an inverter that used two, count'em, two, output transformers, each driven by a plain vanilla square wave, but they were in series, and the regulation took place by controlling the phase of the two square waves - 120 times a second, the two secondaries flipped from "buck" to "boost". The output waveform was essentially a positive pulse, then zero, then a negative pulse, then zero, then another positive pulse, and so on.
It ran everything we plugged into it, even an induction motor bench grinder. Lamps are trivial, and series motors, like a hand drill, don't care.
We didn't plug a computer into it, however, or anything with an SMPS, so I guess my recommendation would be to check the spec on what it is you're plugging into it.
Good Luck! Rich

In alt.solar.photovoltaic Steve Spence wrote:

I believe "stepped sine wave" to be an oxymoron.

I (obviously) don't agree with that. Gotta call it something. It's not a sine wave, but if you squint at the oscilloscope a little, it looks more like a sine wave than a square wave.

UPS (uninterruptable power supply) isn't so wrong, as from the computer's POV, the power never was interrupted.

Ah, from a particular Point of View... if that's the criterion, then the square/modified/lumpy/sine wave is a sine wave for most applications.
-- --- Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8,-122.5

"philkryder" wrote in message

Steve - How many equal "steps" are necessary for the MSW inverter to be a sufficiently close approximation to a "rotary" sine wave?

Careful. Even true 'rotary' generators don't always put out a true sine wave.
Even the very, very large commercial generators used in power plants, don't put out a 'pure' sine wave. The number of stator slots and rotor geometry cause a small amount of harmonics. The exact connections of windings is often used to help improve the fundamental and minimize some of the higher harmonics (6th, 9th and 11th are some of the more troubling ones).
After it passes through several transformers, getting to the substation, most of the harmonics have been filtered out by the characteristics of the transformers.
So the question, as usual, boils down to 'how good, is good enough?'
daestrom