Hi Becalmed.
I have been running a 6kW OzInverter from September of last year, it hasn't missed a beat, and does not get hot. It even sits in a covered cubourd on an exterior wall, so it got the -20c below and +30c, sun, wind, and rain. Testing of course, not advisable for normal mounting.
I love it.
Originally I purchased an expensive, what I thought was the Rolls Royce of Inverters, by a well known manufacturer, (I cant tell you who it was, as they have a gagging clause on me now, just so I could get my money back).
Well, when it was back charging just a little bit the HZ would go stupidly high and domestic applainces would fail. The manufacturers comment, "Buy all are ancillary equipment to stop this". Basicly a lock in. Just Nuts!
So with Oztules help I have a Robust, Simple, and very importantly very cost effective World beating 48v dc to 230ac, 50HZ,pure sine wave Inverter.
Please remember I have very little electronics abilities, and boy what a steep learning curve that is, but 'oztules' helped in giving a hands on empirical evidence.
The 6kW OzInverter, used 2 off stacked toroid cores of 190mm outside diameter, 90mm diameter centre hole and 60mm high, and these two gave us 120mm high core, or a section through the core of 100mm x 120mm. 4off/4 in hand 118 turns of 1.8mm diameter enamelled copper wire as the secondary windings, and 14 turns of 50mm/2 insulated copper cable as the primary winding.
For the BigOzInverter No2, I am using 2off cores, 230mm outside diameter, 100mm diameter centre hole and 70mm high. Stacked/joined together, gives us 140mm high core, or a section through the core of 130mm x 140mm. The windings will be, 5off/5 in hand 80 turns of 1.8mm diameter enamelled copper wire as the secondary windings, and 10 turns of 70mm/2 insulated copper cable as the primary winding. When finished, this larger toroid will be about 42kgs/91lbs in weight.For real working data & calculations on the core........ see.
http://www.anotherpower.com/board/index.php/topic,1117.0.html?PHPSESSID=h7jd5l4edljl6k4ls18pgfj4i1 I think for clarity it should be remarked that the OzInverter should be seen in the whole.... Get the Toroid right....
Reasons for this design of Toroid. Why don't we just buy a toroid transformer ready made? Ahh, that's where this toroid design wins hands down.
1. We double, treble, quadruple stack the cores. Keeps the copper loss down, but increases the core mass so its cooler and can handle more. But, now's here the sting, the core centre is now too small, because of its double stacked height, for a normal commercial toroid manufacturing winding machine to get in. So this design has to be hand wound.
2. After each secondary winding, we Epoxy the winding before putting the next layer of Mylar insulating tape on. Its not to heavy coating, but this stops the windings from vibrating, rubbing together and eventually failing, it also helps with cooling.
3. As this design is hand wound, the Primary small number of turns can be the full size big diameter cable. This also helps significantly with keeping the toroid cool as this winding is open, and air flow can easily circulate around and through the toroid.Get the Electronics, Control & Power Board right, but this must be thought out......Ease, simplicity, robustness of manufacture........ease of cooling the boards and keeping moisture away, so effective mounting is important. ......Cooling system is important, again Oz's cooling circuit works very well, my 4 fans, and its rare that i see them all on and working flat out.
We have come away from PowerJack Boards, because of the Uncertainty of supply and serious QC issues. There is nothing wrong with the PJ 15kW boards, but like me Oz would rather be in total control of the manufacturing process and not beholden to any maufacture......
Again Oz has thought out all the parts for the Boards and that they are readily obtainable. At present my stumbling block is the GERBER files for the Manufacture of the New 6kw-15kW Power board. Individual manufacture as DIY job with Masks is now complete and I will post soon.
The E choke is important and this brings down my idle power use to just 45watts, now, for a single winding that's pretty darn good.
Internal Cabling, both DC & AC, EMC filters, and RCD for the 230vac output are all important and need to be approached in the correct way.
In Conclusion...... Most of my life I have looked at Inverters and wondered. I made a little 200w toroid 30 years ago.
But this OzInverter is a life changer, not just for folk like me, but this project gets a real working cheap Inverter out of the clutches of the Corporations and vested interests.
And Boy do some not like this concept, yes I get weekly abuse about my Book, even the ISBN number has been with held because of complaints from the so called professionals.
The detailed book/manual is about my construction of a 6kW OzInverter, and the Big OzInverter, with chapters for each distinct construction stages. I have also added separate instructions and appropriate comments from ‘Oztules', John Tulloch, Flinders Island, Australia, who's jottings, 60,000 words, are open source on the World Wide Renewable Energy Forums … http://www.anotherpower.com/board/index.php …….. http://www.fieldlines.com/index.php , and http://www.thebackshed.com/forum/home.asp When I get the PCB boards back from the manufacturers, just 20, and tested I will put a link up on our site and hopefully, with permission of the Moderators, post a link here.
Good luck 'bcalmed' and enjoy the voyage.... I certainly have........