Newer designed inverters

MEXICOWANDERER wrote:
The measure of a good inverter is accurate trouble-free operation for many years. And I gotta de gnus for you...designs that utilize good old fashioned heavy weight copper-wound transformers are light-years more reliable over the long run.

I agree with the first half of your statement adding "at a reasonable cost", but I disagree with the second half.

MEXICOWANDERER wrote:
Truly sturdy solid state synchronous inverters are nightmarish expensive.

In a former life I was a EE. Recent improvements (> 2 years) in power MOSFET transistors, mean less losses to heat. The big win are dedicated integrated circuits that handle the "bulk" of the conversion ( 1) stepping up to high voltage, 2) making a true sine wave)

MEXICOWANDERER wrote:
One does not build reliable solid state electronics with borderline voltage and capacity rated components. I elected to go with 350 volt 680 ohm Panasonic capacitors instead of 200 volt originals, Bi-Polar transistors rated 33 amps at double the voltage, and 80 amp 150 volt Schottky rectifiers rather than the original 20 amp 100 volt TO247 devices. Wanna shock? Price the difference. Wanna bigger shock? Have a Megawatt go bad 2,500 miles from the US border.

So you DO know a thing or two about what is going on inside !

What is wrong with Power MOSFETs over bi-polar ? Sized properly (or I should say "over sized" properly) there is no reason why they should not last as long a a bipolar transistor.

MEXICOWANDERER wrote:
But alas for techo-addicts it has a heavy-assed copper transformer.

I'll buy stock in copper mines.

You can't make power out of nothing. That's for sure.

However, some "gullibles" are still sold on the sales pitch that inverters can boost the shortfall that their existing power source can effectively deliver.
But, by all means keep buying them. . .my portfolio manager sent me an email saying he just bought some shares in Eaton Industries (ETN). The largest supplier of inverter components for consumer and the military.

I have to say that turning 450 volts dc into 240 volts AC is pretty trivial, and to my mind is not at all inverting, it is simply converting.
I consider a couple of things to be the "newer" tech- the basic is simply doing the actual inversion at a very high frequency, so you can use small transformers- chop the 12 volts at 10 kHz, bump up to ~120 volts, rectify to dc, chop at 60 Hz.
More important to me is new software and sensing, adding support capability to augment when needed.

The point is, there IS newer technology out there, better and less expensive than the designs that Xantrex, Samlex and other have been selling for the past 10+ years.

That is the hyperbole
Mfg want to save money, if it's cheaper to make something they Will do it !
Getting more power reliably out of a smaller package is Not less expensive

Also the smaller more expensive device is not going to get a lot more power out ANY battery bank than the bigger bulkier older device design
Maybe 91 percent instead of 90 percent
You can't make power out of nothing, you can't get more power than what is stored in the battery bank

The measure of a "Good" inverter is not whether it can develop 10,0000,00,000,000 watts for a half cycle. This is utterly stupid rhetoric.

The measure of a good inverter is accurate trouble-free operation for many years. And I gotta de gnus for you...designs that utilize good old fashioned heavy weight copper-wound transformers are light-years more reliable over the long run.

Truly sturdy solid state synchronous inverters are nightmarish expensive. The cost of the transcribers on DC power lines cost more than six square blocks of residences in your home town. One stupid thyristor costs $57,000 dollars.

One does not build reliable solid state electronics with borderline voltage and capacity rated components. I elected to go with 350 volt 680 ohm Panasonic capacitors instead of 200 volt originals, Bi-Polar transistors rated 33 amps at double the voltage, and 80 amp 150 volt Schottky rectifiers rather than the original 20 amp 100 volt TO247 devices. Wanna shock? Price the difference. Wanna bigger shock? Have a Megawatt go bad 2,500 miles from the US border.

But the stuff has to last, or it's a laff. A one off, single 100 meter dash performance that is supposed to inspire is ludicrous. It is what (?) 2% or so along on the road to relevant significance.

I am all for technological advancement. But I did not buy into the Popular Science "All Moving Sidewalks" in 1956, and sixty years later I am still not holding my breath.

I am going to spring for that 3,000 watt inverter with 80-amp charger as a Christmas gift to myself. But alas for techo-addicts it has a heavy-assed copper transformer.

Landfills are full of toxic chew and spit electronics. Every time some is recycled it consumes an enormous amount of energy. When are people going to wake up to this fact? Build it once, build it right and don't spew thousands of pounds of CO2 returning, recycling, and hypnotizing oneself with illusions of grandeur.

There's no info here for a reader to make his own evaluation if there's really new/better technology or if it's just hype. As general statement, an inverter that has a DC input higher than the peak of its RMS AC output is a lot simpler than one with a lower voltage DC input that has to stepped up using either a big transformer, or a second inverter and a small transformer. The Honda inverter generators are a 15 year old design and so far there doesn't seem to be a newer competitor that outperforms. To the question of which companies build with newer technology, I don't have the answer, but the first place I'd look is the solar industry microinverters. They have an impressive array of features, high efficiency, good reliability, and reasonable cost in a fairly small package. I'd guess that a lot more than a million went into their design.

MrWizard wrote:
I think you have let the hyperbole confuse you

Yes you can get 5000w from 12v input, just not from one battery, unless you only want it for a few seconds
It simply more effective to use higher input dc voltage to create the ac output.

No, I am not confused and I do understand those inverters on eBay will never preform near the advertised ratings or as you said for more than a few seconds.


The point is, there IS newer technology out there, better and less expensive than the designs that Xantrex, Samlex and other have been selling for the past 10+ years.

I think you have let the hyperbole confuse you

Yes you can get 5000w from 12v input, just not from one battery, unless you only want it for a few seconds
It simply more effective to use higher input dc voltage to create the ac output
Lower amps high volts smaller wire

Inverter generator used high voltage dc from an alternator to create the 120vac output

When some one finds a way to change inductive loads into resistive loads, then truly small high power inverters can become a reality