My turbine power wall

[fabricator]

OK I just tried that on the busses in the box, and got an unexpected result, between the hot and neutral I get 223, between the hot and ground I get 123 and between the neutral and ground I get 123, I thought you couldn't get 110 out of the 220 model, but maybe if you do that you will damage the thing somehow.

[ChrisOlson]

OK I just tried that on the busses in the box, and got an unexpected result, between the hot and neutral I get 223, between the hot and ground I get 123 and between the neutral and ground I get 123, I thought you couldn't get 110 out of the 220 model, but maybe if you do that you will damage the thing somehow.

That's what I get out of my 240 volt one too, except I was getting closer to 237.  But that's normal for 240 volt split phase.  What I'm curious about is your 120 volt one, if that has any power on the neutral wire.

I think you could run a very small 110 volt load on one leg without hurting it, but you don't have a ground with 240 volt split phase.  You got two legs and a neutral.  A motor will run fine without the neutral wire, which technically doubles as a ground.  But it's not a true ground because you got no Ground Fault Protection like is required on 120 volt.
--
Chris

[fabricator]

the 120 has 113.5 from hot to neutral and 78.2 between hot and ground and neutral and ground.

[ChrisOlson]

the 120 has 113.5 from hot to neutral and 78.2 between hot and ground and neutral and ground.

Hmmm.....  So those are different than my Schumacher inverters then.  I'd be curious to know if the voltage changes under load or not on those too, but I assume you measured that with the inverter at least partially loaded, or driving some lights or something?  Or was that totally unloaded with the unit in idle mode?  I don't know how the heck they're getting 78.2 volts on two legs to add up to 120 (or 113, or whatever).  If both legs were like 60 and you had 120 between them that would make sense.

Do those 120 volt units have Ground Fault Interrupters, or just a circuit breaker for overload?

Edit:
I guess I'm curious as to the GFI protection on those 120 volt Accurate Tools inverters because of the UL requirement, which is if there's a 5 milliamp leakage on the "hot" (or difference between neutral and hot) it trips and shuts the power down.  As far as I can tell, my Schumacher units meet every requirement to be UL Listed complete with GFI plugs with "test" and "reset" buttons, but I cannot find a a single mark on it anywhere that says they are, nor in the manual for them.  Testing an outlet in the house, with the system loaded with nighttime lights going and whatnot, I get 110 volts on the hot to ground and it does show .05 volts on the neutral to ground.  I don't have a grid connected system here to test to see if that's "normal" or not.
--
Chris

[riahserf]

Altough my inverters are a different brand

My posts had nothing to do with being tied to the grid, mains, neutral, or ground.

The Vecter inverters I have, have tags on them stating "do not bond the neutral to ground or damage will occur".... but one day while doing some testing I shorted the neutral to ground. Everything shut down,... and a little magic smoke came out of the inverter. So I disconnected everything... and under ferther inspection found the three fuses blown on the inverter. Well it was only about a $25 inverter, so... put three new fuses in and hooked it back up.... turned it on ... now ALL the smoke came out!

So when I saw your nice looking wall, and that little breaker box,... brought back memories.

This inverter has between 67.7 and 68 volts on the hot and the neutral


-Ed

[ChrisOlson]

but one day while doing some testing I shorted the neutral to ground. Everything shut down,

I had a Cobra 800 watt inverter in my RV that I did that with once.  It made a snap in the inverter like a circuit breaker inside it had tripped.  I took it apart and the internal fuses were good, could see nothing else to reset or anything wrong looking in there, the green light came on normally - but no AC power would come out of it anymore.

When I tried it with my Schumacher inverters all it did was trip the GFCI.  Press the button to reset it and it fired right back up.
--
Chris

[JoeD.]

In the photos in the first post, the picture of 2 inverters feeding a breaker box. You've tied the two "Line" (hot) wires from the AC output of the converters together at the breaker, and the neutrals together on the neutral buss, and the grounds are tied on the ground buss. The 2 units are paralleld Therefore you get 120vac out of that small breaker box the way it is set up.

  Is is not feasable to have one inverter for one leg and another inverter powering another separate leg in the electric system in your home- or whatever you are powering? 

  I guess what my question is~ "can separate inverters share neutrals and grounds in your electric system"?

  From first glance at the photos, I thought that is what he was doing. That is, until I looked closely at the small breaker box.

  What is going on with the third inverter (on the left). I didn't understand that from the posts. What reason for it feeding a breaker box all its' own. Maybe I missed it in the conversations....

[ChrisOlson]

In the photos in the first post, the picture of 2 inverters feeding a breaker box. You've tied the two "Line" (hot) wires from the AC output of the converters together at the breaker, and the neutrals together on the neutral buss, and the grounds are tied on the ground buss. The 2 units are paralleld Therefore you get 120vac out of that small breaker box the way it is set up.

I'm not Dale (fabricator) but I just looked at that photo and Dale has those inverters wired wrong on the AC side.  Those are stacked (networked) 240 volt inverters and the black and white are the two legs, and the green is the neutral.  There should be a two pole breaker in that box with the two blacks hooked to one pole, the two whites hooked to the other pole, and the green hooked to the neutral bus.

The panel should then be grounded with a bonding screw that ties the panel to the system ground rod.

The way it's hooked up right now only one leg of the 240 split phase is fused, and if the circuit is overloaded it will trip the breaker on that one leg but the other leg will remain hot.

 

What is going on with the third inverter (on the left). I didn't understand that from the posts. What reason for it feeding a breaker box all its' own. Maybe I missed it in the conversations....

That inverter is a 120 volt and it requires a separate panel because these inverters only come in 120 volt and 240 volt models, not a 120/240 combined.
--
Chris

[fabricator]

In the photos in the first post, the picture of 2 inverters feeding a breaker box. You've tied the two "Line" (hot) wires from the AC output of the converters together at the breaker, and the neutrals together on the neutral buss, and the grounds are tied on the ground buss. The 2 units are paralleld Therefore you get 120vac out of that small breaker box the way it is set up.

I'm not Dale (fabricator) but I just looked at that photo and Dale has those inverters wired wrong on the AC side.  Those are stacked (networked) 240 volt inverters and the black and white are the two legs, and the green is the neutral.  There should be a two pole breaker in that box with the two blacks hooked to one pole, the two whites hooked to the other pole, and the green hooked to the neutral bus.

The panel should then be grounded with a bonding screw that ties the panel to the system ground rod.

Since that photo was taken I had one of those forehead slapping moments, its wired like you described now, I even drove down two eight foot ground rods eight feet apart, bonded them together with bare 8awg and connected to the inverters with 8awg and copper split bolts to the wire between the ground rods

The way it's hooked up right now only one leg of the 240 split phase is fused, and if the circuit is overloaded it will trip the breaker on that one leg but the other leg will remain hot.

 

What is going on with the third inverter (on the left). I didn't understand that from the posts. What reason for it feeding a breaker box all its' own. Maybe I missed it in the conversations....

That inverter is a 120 volt and it requires a separate panel because these inverters only come in 120 volt and 240 volt models, not a 120/240 combined.
--
Chris

[dnix71]

The 60 up and 60 down makes sense. I have a cheap sine wave inverter from AIMS. If I overload it it doesn't quit, but the voltage drops to 60 and sits there until something else gives. I use it to power sensitive but very light loads. When I'm finished with it I plan to destroy it so someone doesn't do damage because of it's design/manufacturing defect. Dead shorting the unit into a box freezer compressor trying to start up didn't trip anything. I had to manually turn it off.

[JoeD.]

  I guess I read that but didn't put 2 and 2 together. I was thinking that maybe those two were 120vac units stacked together and feeding their individual 120 v. legs and neutrals into that box and he wanted to take 240v. out. In other words one black should've been on one breaker, and the other black on the other breaker, and I thought the white wire were neutrals.

  So, back to my original question. Would doing that be possible? One generator/inverter feeding 120v to one buss in a 240v panel, and another generator/inverter feeding 120v to the other buss, and both of their neutrals tied together on the neutral buss.

  As long as you didn't try to connect a 240 volt load across the system anywhere, you'd be fine, wouldn't ya? The two systems wouldn't even know they were working side by side? Since no 240 v. load would be connected, the fact that they wouldn't be synchronous with each other wouldn't come into play.

  Let me edit this to reflect the fact that my idea is predicated on my assumption that there is no volatge from neutral to ground on these inverters. This could make for some serious smoke release Some previous posts discussed voltage in between those two points. I have no clue why there would be, but in this specialty electric equipment, who knows?

[ghurd]

  Let me edit this to reflect the fact that my idea is predicated on my assumption that there is no volatge from neutral to ground on these inverters. This could make for some serious smoke release Some previous posts discussed voltage in between those two points. I have no clue why there would be, but in this specialty electric equipment, who knows?

But there IS voltage from Neutral to battery negative.  Or ground if the battery negative is grounded.

The inverter expects that -60V on the "neutral" to go through some controls and a load before reaching the +60V on the hot.
If the 2 inverters are 180 degrees out, then one neutral is +60V and the other is -60V, and they are connected together.

Yes.  Massive quantities of Magic Smoke.
G-

[joestue]

I guess I read that but didn't put 2 and 2 together. I was thinking that maybe those two were 120vac units stacked together and feeding their individual 120 v. legs and neutrals into that box and he wanted to take 240v. out. In other words one black should've been on one breaker, and the other black on the other breaker, and I thought the white wire were neutrals.

  So, back to my original question. Would doing that be possible? One generator/inverter feeding 120v to one buss in a 240v panel, and another generator/inverter feeding 120v to the other buss, and both of their neutrals tied together on the neutral buss.

  As long as you didn't try to connect a 240 volt load across the system anywhere, you'd be fine, wouldn't ya? The two systems wouldn't even know they were working side by side? Since no 240 v. load would be connected, the fact that they wouldn't be synchronous with each other wouldn't come into play.

  Let me edit this to reflect the fact that my idea is predicated on my assumption that there is no volatge from neutral to ground on these inverters. This could make for some serious smoke release Some previous posts discussed voltage in between those two points. I have no clue why there would be, but in this specialty electric equipment, who knows?

The issue is and I have said this before in prior threads: 12 volts is converted into 120-170. this is referenced to the dc ground, or half way in between. (+70, -70)
this dc voltage is filtered with a 200 volt capacitor and converted into ac with a simple hbridge. often these h-bridge fets don't even have heat sinks on them, or they are soldered to the board.

Some inverters are easy to snip the traces that connect the 120-140 vdc side to the battery. others don't use optical isolators or pulse transformers to close the loop, they use two resistors to save 50 cents, these units you can't simply disconnect because there would be no way for the inverter to regulate the 140 vdc side.

[ChrisOlson]

  So, back to my original question. Would doing that be possible? One generator/inverter feeding 120v to one buss in a 240v panel, and another generator/inverter feeding 120v to the other buss, and both of their neutrals tied together on the neutral buss.

Yes, you can do that.  I have two Schumacher inverters paralleled just that way, powering a 240 volt panel (with no 240 volt circuits in it), with each inverter "hot" hooked to each of the power busses, the neutrals from both hooked to the neutral bus, and the grounds connected together at the ground bus.  It works fine and is the recommended method for off-grid systems, in the absence of split-phase power, to power branch circuits in the house that use a shared neutral to prevent overloading the neutral wire from both the "hots" being in-phase.  You just make sure that when you connect parallel inverters that are not phase-synced, that you take care in wiring your panel so that branch circuits that use a shared neutral have the "hots" on separate buses in the panel.

Dale cannot do this with his 120 volt inverter as they carry voltage on the neutral, which means with potential between the neutral and ground they have no internal neutral to ground bond.  He can, however, stack them with a networking cable that phase synchronizes the two inverters.  Basically, all those networking or "stacking" cables do is disconnect the 60 Hz drive to the FET's in the slave unit and use the drive from the master unit to put the two units in sync.
--
Chris

[fabricator]

OK folks, DO NOT USE THESE INVERTERS, they are total junk, they have one time ground fault protection, one ground fault and the inverter is smoked, the 120 volt versions don't even have that, these inverters cannot in any way be made to meet the NEC, I'll see if Chris Olson will post a better explanation here, he talked to the seller on the phone, they will replace a blown inverter but will not give refunds.

[ChrisOlson]

Dale I posted what I found out in a Reviews thread:
http://fieldlines.com/board/index.php/topic,144200.0.html

--
Chris

[mcline27b]

There have been a lot of questions about the waveform output of the AccurateTools ATSIU-2500P "Semi-Pure Sine Wave" Inverter.

I picked one of these units up after reading comments such as "Even in idle mode it's not real blocky like a cheap modified sine inverter is.  But it definitely cleans up when you put a load on it."  I put mine on the scope and found exactly the opposite, namely that under any load condition the output is completely square, or more technically MSW.  It does not look like a true sine-wave in any way.

Attached are a no-load trace, a 100W load trace, and a 1000W load trace, all non-reactive loads.  Notice the inverter adjusts the "off time" downward as the rail voltage drops.  It's a great inverter, but the output is no cleaner than any other Modified Sine Wave MSW inverter.  "Proprietary SPSTM (Semi-Pure Sine Wave)" seems to be no more than marketing buzzwords.

No Load

100 Watt Load

1000 Watt Load

[ChrisOlson]

I picked one of these units up after reading comments such as "Even in idle mode it's not real blocky like a cheap modified sine inverter is.  But it definitely cleans up when you put a load on it."  I put mine on the scope and found exactly the opposite, namely that under any load condition the output is completely square, or more technically MSW.  It does not look like a true sine-wave in any way.

Try running an electric motor with it.  I had my Sun scope on the one I had and it wasn't a perfect sine wave driving my well motor but it was clean enough so the motor didn't hum under load and it pretty much looked like a real sine wave to me.

Even my Schumacher inverter, which has a very blocky sine wave under no load, has what looks almost like a pure sine wave when running my drill press motor with it.

I sold my Accurate Tools inverter to a fellow who's using it to run a small MIG welder so I can't go back and test it some more now.
--
Chris

[rossw]

Attached are a no-load trace, a 100W load trace, and a 1000W load trace, all non-reactive loads.  Notice the inverter adjusts the "off time" downward as the rail voltage drops.  It's a great inverter, but the output is no cleaner than any other Modified Sine Wave MSW inverter.  "Proprietary SPSTM (Semi-Pure Sine Wave)" seems to be no more than marketing buzzwords.

I'll no doubt get hounded, lambasted, ridiculed and told I'm not allowed to have an opinion because I'm a mod, but the photos demonstrate exactly the reason these sorts of inverters should be avoided like the plague. There's not a single good thing about them IMO.

Anyone who recognises what "DV/DT" is, and the implications of it, need no explanation. Those who don't and CBF to look it up won't be told otherwise either.

Even a feisty old LC filter on the output would make them less disasterous - however that would sap some energy, and cost more money.

In this day of embedded electronics turning up quietly in all manner of things you wouldn't have expected, you can be pretty sure that sooner or later, one of these PoS are going to let the magic smoke out of something you need. (And I don't specifically mean this *BRAND*, but this *TECHNOLOGY*. 

The very fact that they refer to it as "Semi-Pure Sine Wave" means clearly they KNOW people want pure-sine and are actively engaging in deceptive marketing to fool people into buying something they wouldn't touch were it honestly marketed. </opinion>

[fabricator]

Since I originally started this thread I've learned a lot about the accurate tools inverters, in my opinion they are dangerous junk and should not be used in any situation and importer who advertises them as fit for use in home power situation on Ebay should be charged with fraud and/or sued out of existence.
However, that is not intended to paint all modified sine wave inverters the same color because they clearly are not, a lot of people all over the world use modified sine wave inverters successfully in a lot of different applications, but it's like they say, "Opinions are like aholes, everybody's got one"

[rossw]

"Opinions are like aholes, everybody's got one"

You're obviously just spoiling for a fight. I take offence at your comment and the implication.
You went off the deep end for me referring to someone as a VI (not generally considered offensive in my country), yet you call me an arsehole. You hypocrite.

[SparWeb]

Mike,

Thanks for going to so much trouble to test the inverter and post results.  It is easy to leave an opinion unquestioned, much harder to go to the effort to find out for yourself.  I see you even signed up to FL just to post this paritcular fact, therefore I welcome you very warmly to the group!     I hope you feel welcome and can contribute more.


To some others:

Enough hot air.  Many readers of certain recent exchanges have not been impressed and I don't want to hear it start again.  You are taking personally something that is mostly technical.

[mcline27b]

Thanks for going to so much trouble to test the inverter and post results.  It is easy to leave an opinion unquestioned, much harder to go to the effort to find out for yourself.  

My pleasure...  I had searched all over the web for what exactly this "Semi-Pure Sine Wave" was without finding a definitive answer, and like many others I "wanted to believe" that something short of pure sine could be close enough.  It's too bad that the physics side of things makes it impractical and inefficient to generate anything other than square looking waves, and likewise makes it impractical/inefficient to utilize anything other than sine-looking waves in most devices...  Either way, this and other MSW inverters will work good enough for many of the things I wanted to power (like my fridge/freezer/gas stove blower/fluorescent lights, etc.), and would probably work fine on the items I won't test it on, like my LCD HDTV with switching power supply.

I do wish there were more truth in advertising however, and I hold this against AccurateTools using terms such as "Semi-Pure Sine Wave" and giving no meaningful or accurate definition of what that means.

By the way, this board (in conjunction with Wikipedia) has been very informative to me about alternator design.

Michael

[fabricator]

I guess reading comprehension is also not one of your strong points.
OK, look here Ross, we all know you and Dan B have complete disdain bordering on contempt for anyone not using a 48 volt pure sine big name inverter, in your and Dans stated opinion in another thread 12 volt systems are third world clunky systems, 24 volt systems are a slight step ahead and qualify as wannabe systems and the 48 volt is the gold standard.
Whether or not you realize it or not you just alienated about 98% of the members of this board, very few of us can afford one hundred thousand dollar plus off grid systems
so please try to keep your contempt for anyone not having such a system to yourself and things will be all rainbows and sunshine.

[fabricator]

Thanks for going to so much trouble to test the inverter and post results.  It is easy to leave an opinion unquestioned, much harder to go to the effort to find out for yourself.  

My pleasure...  I had searched all over the web for what exactly this "Semi-Pure Sine Wave" was without finding a definitive answer, and like many others I "wanted to believe" that something short of pure sine could be close enough.  It's too bad that the physics side of things makes it impractical and inefficient to generate anything other than square looking waves, and likewise makes it impractical/inefficient to utilize anything other than sine-looking waves in most devices...  Either way, this and other MSW inverters will work good enough for many of the things I wanted to power (like my fridge/freezer/gas stove blower/fluorescent lights, etc.), and would probably work fine on the items I won't test it on, like my LCD HDTV with switching power supply.

I do wish there were more truth in advertising however, and I hold this against AccurateTools using terms such as "Semi-Pure Sine Wave" and giving no meaningful or accurate definition of what that means.

By the way, this board (in conjunction with Wikipedia) has been very informative to me about alternator design.

Michael

One very important thing to know about these inverters is they have one time ground fault protection, and after that one ground fault event the inverter is smoke out junk.

[rossw]

It's too bad that the physics side of things makes it impractical and inefficient to generate anything other than square looking waves

It's not really impractical.

The vast majority of pure-sine inverters actually generate something not greatly dissimilar to the waveform you indicate - except that instead of doing it at 50Hz or 60Hz, they do it at a frequency 500 times higher - often around 30,000 Hz.

Using PWM (pulse width modulation) they create a "square-wave" whos average value is the required voltage for that particular phase of the 50/60Hz waveform. By doing it so quickly means quite practical sized filters can remove the high-frequency component and you're left with a nice, clean sine wave.

Granted, these become a little more complex, and a little more expensive, but it's certainly both practical and efficient.

[rossw]

I guess reading comprehension is also not one of your strong points.

you really are an arrogant, hypocrital SOB, arn't you.

OK, look here Ross, we all know you and Dan B have complete disdain bordering on contempt for anyone not using a 48 volt pure sine big name inverter

It's clearly you that has the comprehension problem.

I've said it a dozen times, you either can't read, or won't read... but let me try one more time.

I HAVE NO PROBLEM WITH 12V SYSTEMS IN THE RIGHT APPLICATION. (Or 24V, or 36V, or any voltage for that matter!)

in your and Dans stated opinion in another thread 12 volt systems are third world clunky systems

Another misquote.

Whether or not you realize it or not you just alienated about 98% of the members of this board

So you'd rather hijack a useful thread and repeatedly insult me in public. Classy.

very few of us can afford one hundred thousand dollar plus off grid systems
so please try to keep your contempt for anyone not having such a system to yourself

Adding gross over-exaggeration to incomprehension. Is it a race to the bottom?

and things will be all rainbows and sunshine.

I doubt it. You're going to go out of your way to slag me of at any opportunity. You've done so every chance you get so far, I see no reason for your attitude to change. You're incapable of, or unwilling to, see what's being said and would rather take things as a personal affront when they weren't, and misquote and exaggerate to inflame any situation. I suggest if you want to continue it, you do it without hijacking threads and bringing the whole tone of the board down.

[fabricator]

And now we have the pot calling the kettle black, how bout a deal, you quit slagging anything but pure sine big name hundred thousand systems and
I won't have to open my pie hole.

[TomW]

OK, guys;

I respect you both and you both do so lets chalk this up to what I believe it is:

A complete misunderstanding caused by different folks on different sides of the planet with a common language and where meanings are vastly different.

I have a 24 volt system and both a cheap Accurate Tools for my well in emergencies and a 24 / 7   Outback 2524 Pure Sine high end inverter I trust with my freezer and other 24/7 loads.

I am in the middle all around on this discussion and I just want you guys to swallow the slug of pride or whatever, shake hands and agree to disagree. Here I would call it "man up" and get back to the subject at hand.

It is unfair to everyone who is interested in the subject at hand. No harm and no foul if this skirmish goes away now.

Anyway, that is all I will say so make my job easy and pick on me!

Tom

[DanB]

Damned...
It's OK actually ~ I have a few dogs, and my neighbors have dogs... and I like them all and for the most part they like one another but everynow and then somebody has to throw a a 5 gallon bucket of water on the pile.

Seems to me everyone here has their points.  I (in my own defense) do not have a problem with 12, 24, or 48 volt systems - or cheap inverters.  The ones on Fabricators wall are very interesting actually...

I'll just repeat what I've said before though...
12 Volt systems have their pros and cons.
Cheap (inexpensive) inverters also have their pros and cons.  If it's not UL listed ~ odds are it's not going to get 'signed off' by your electrical inspector and it wont be 'legal' ~ so - it depends on what your goal is.  If your house burns down, and the system is not 'up to code' then...  insurance may not pay.

All that said - I'm certainly the most guilty perhaps of owning a system that is not up to code!

Big expensive inverters cost more - but they probably work better, they take big surges longer and they have features (bells and whistles) which some folks may find valuable (others may have no need for them... I actually dont, even though I have one of those sorts of inverters)

The ones Fabricator has here are real interesting, the feature of them all talking to one another is pretty neat ... so is their price.  If I was building an off grid home though, and it came time for the inspector to drop by - they wouldn't fly. 

Heck I don't know.  I'm very grateful for fabricator posting this story - it's a nice system with interesting components (when my old trace dies... if it dies, I may go that route).  I'm not really quite sure what the whole pissing contest was about to begin with but hopefully in a few days everyone forgets and remembers how to get along! 

[ChrisOlson]

If it's not UL listed ~ odds are it's not going to get 'signed off' by your electrical inspector and it wont be 'legal'

UL Listed don't mean much, really.  My wife had a 140 watt curling iron that was UL Listed so she could put these cool looking waves in her hair, or whatever.  That curling iron, which is supposed to be double insulated and whatnot because it's UL Listed got a short in it.  She got a shock off it.  If it wasn't for my non-UL Listed inverter shutting itself down within milliseconds when it sensed the ground fault in that curling iron, her hair would have permanent curls and she wouldn't need no curling iron anymore.

But I have to admit - that was the same curling iron I dropped in the bathroom sink full of water one day to test the ground fault sensing in the inverter.  I may have damaged that curling iron when I did that because it sizzled pretty good.   
--
Chris

[fabricator]

Dan, you might have missed one of my posts in all the dust, when I originally started this thread, these things looked really good, stackable, affordable, since then I have learned a lot about them, in short they are junk, they have one time ground fault, after one event the inverter is dead.
The person who calls himself "support" has no idea what the difference is between earth ground and neutral, in order for an inverter to meet NEC requirements the chassis earth ground must be bonded to the neutral in the inverter, just like the service entrance in a house, if you hook one of these things up to a breaker panel or transfer switch and bond what they call the neutral leg to what they call the ground wire the inverter dies a smoky death.
There are mid range inverters like AIMS and Samlec that fully meet the NEC requirements regarding earth ground and neutral.

[tanner0441]

Hi Chris

These waves it puts in her hair are they sine wave or square waves.

Brian