Author Topic: Building a 6kw pure sine wave inverter using power jack boards part1 transformer  (Read 120250 times)

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oztules

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The 15kw boards are a good match. You really only need one unit for 220 and 110v... the only proviso is to balance the phases as best you can..... remember only one active leg will be giving the controller the info it needs in order to control the current..... no matter if you build two or one unit.

If you don't balance the loads per phase, anything is possible, as it can over control or under control depending which leg is using the majority of the current being noted.

If you were able to measure the input current ( DC), and replace the voltage generated by the Ac CT then you would have no problems I expect


............oztules
Flinders Island Australia

Neil

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Thanks oztules  I'm going to order one of the pj 15kw units with the split phase and see what there doing to get the split phase.

Neil

oztules

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Here is an updated pin out of the PJ control card.... updating the mistake on the other pic a page back
The pin 1 is 5v not 12v. It is the chip bus so is only used by PJ harnesses for their led lights... don;t use it for the fans.... use the front 2 pin plug where it says adjust.

9160-0

Courtesy of Glen at the back shed who has just finished one of his own... here
 http://www.thebackshed.com/forum/forum_posts.asp?TID=7800&PN=1&TPN=1

oztules
Flinders Island Australia

jan04

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Sorry for hooking up here again … the idea with one welder transformer was not very yielding. my old welder transformer can only serve about 16v x 45A continuously. I'm sure a good cooling will help, and it will be able to drive about 19v x 115A, but the loss would be overwhelming. That's not good  ;) After another round look up yesterday, i had a little bit more luck today. I've got one used industry charger of sparse remainders from ex telekom stock. It serves 40A by 48V/49,4V/53,4V/58,3V. In my opinion a very respectable installation, and old school manufacture. The device works quiet and confident and pushes diligently 40A into the batteries. Problem solved.

The mainboard and the controller i have also repaid. After replacement a couple of resistors, 2 NPN's, 2 PNP's, one 2222, one opto  and 24 FET's the device went to work again. Have a good backup device now. Problem solved.

The next task coms closer... my best half has one idea today  for backing bread in her little nice stone stove. So far so good... after about  50mins the Ankarsrum dough-mashine broke the 10kw PJ inerter to boil. The inverter stoped  working, alarm sounds... overloaded! Basta, nento, nix!

I'd like fresh homemade bread..  this way i need one bigger transformer  ;D


oztules: i'm owner of two toroids, one is 175mm x 90mm x 75mm(high), second one is 175mm x 80mm x 65mm(high).  the question is, can i stack the both? 

rg
jan


oztules

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for 48v operation, a 48v primary is too high... look for around 30v. At higher power, the switchers will have to turn on too long and hard to get the voltage up under sag conditions... ie not enough head room.

These don't monitor input current, only output, so will not see the excessive input current from trying to drive more voltage out than is realistic because of the high primary winding.....

This coupled with the split phase, makes this a problem... it may have been monitoring current on the wrong phase leg... ie no monitoring at all.

Transformer cores.... yes you can.... or look at this a New Zealander is doing.

http://www.anotherpower.com/board/index.php/topic,1066.msg10605.html#msg10605

Now thats old school......

..............oztules
Flinders Island Australia

jan04

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oztules:
"for 48v operation, a 48v primary is too high... look for around 30v. "


no no, that is not the point. i'm sorry i have better to describe my "new" charger. The charger serve the corect VDC power from 48 VDC to 58,3VDC, depend on the batteries condition. that is a aproved full automatical power charger.. this way no headaches.

it seems the point is that the PJ have a small problem with the dynamical loads. wifes dough-mashine gets nominal 800W, but under stress more times, on peaks more then 5kw but for short time aprox. 1-3 sec.  In my opinion the 10kw PJ is a toy for about 3kw continius.. not more. 

thja, the range of usubality skills of the PJ get smaller and smaller..  just take a look, maybe with the bigger one transformer it will be better.. i will report

rg
 jan

oztules

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Sorry to hear that Jan.... but we have not had the same dynamic problems here with the installations done so far......the transformers are the weak link.

There are 8kw units with current bypass  that run 4kw for hours at a time where they have 3.6kw h/w elements plus house loads for the last year or so, so it seems the boards can handle the loads.... but they have substantial transformers on them too. ( ... see transformer articles (here)... I suspect yours was clipping due to voltage sag in the primary perhaps.

That 8kw unit also runs big welders, so dynamic loads are not a problem that we have seen.

So far I have blown up a few units.... but all have been my fault by probes in the wrong place, or dropping the temperature probe ( 30mm s/steel thing) in the wrong place... or experimenting with the charger system ( it's bad with torroids)... but never from overloading them... they should shut down from a short, or after 12 seconds from severe overload..... the one thing i felt they were not.... was soggy or weak, and my home unit can  run 8kw and more without problem... and that has the same fet stage as your 10kw unit i think.. ( 6x4011 per bank).....and the controllers are all the same but for the ct settings.... that I can tell anyway.....

So I can only suspect  a dud board, or the tranny you have built is too light on the primary for the surges you are seeing.. remember it only controls from the AC side, so if it is underdone, it will increase the pulse width without the controller  knowing how much current it is being drawing in the fets.... and it can do severe damage then.... many hundreds of amps.... and if your primary cant convert that to hv ac, then it will give it a bit more........

The 15kw unit here ... well so far has been unstoppable with any loads.... even 10hp induction motors ( 3ph phase converter motor with large sparks from the auto start relays that scare me)..... but solid transformers are a must to try that.


..............oztules
« Last Edit: September 14, 2015, 04:28:27 AM by oztules »
Flinders Island Australia

jan04

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oztules text: "I use a 5v6 zener in parallel with this resistor, as it is just a piggyback and easy to do.
Picture of the resistor is here #59 http://www.anotherpower.com/board/index.php/topic,902.45.html"

...today, a lot of sun.. outback mppt's firing powerfull in the batteries, absorbing voltage over 58VDC... the PJ quit it job again.. without noticeable loads..

i've set up just now one 5.6 zener  in piggy-position ;-) i hope that was...

tnk you oztules for all this usable information.

btw. they have to compilate and sent to each PJ customer the oztules-best-practice-manual

rg
jan

oztules

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I used a5v6 across the R14... but I did not want an outage at any price..... as I was using the grid ties, and wanted to experiment it to death.....

Well death did not eventuate ( even in excess of 258vac ... forced up from the grid tie on purpose) , and I have left it in where it is.

It has been said on other posts that a 1M across R14 will stop the over voltage shutdowns from pwm chargers. I have not tried this, but it may be a better way to go. The 5v6 will stop any control over those functions relying on voltage in the DC section... so the charger will have no idea when to stop i suspect.... with the 1m, most functions to do with DC control will probably still work decently... try that first.


"btw. they have to compilate and sent to each PJ customer the oztules-best-practice-manual "..... if they built them sturdily, with good quality control....and with big transformers matching their power outputs,.... I could not afford to buy them........... so be glad they have such a dubious  name in the industry.  I find them a useful start point, cheap and easy to work on.

They are not for everyone, but the mavericks amongst us who want to play with half decent inverters...... well they are a good place to start. They can be made to be first class with some barbaric modifications.

As you have seen, they are easy to repair in most cases too, particularly if you have fat fingers with bare screwdrivers in the wrong place.... :)

Also..... note.....The cheap fets from china seem to be way off spec in all cases I have bought from, but still very cheap and useful at anywhere from about 4 to 20 MO Rds on.... some even higher still. I buy them in bulk then spend a long time sorting out by Rds. The voltage seems to be fine ( 4110's )... but Rds is all over the place.... beware when replacing them if from china or other less QC conscientious places... match them.... Use the higher rds ones in low power units or other projects.

If you spend some time playing with why the chargers won't work with torroids, you get pretty handy at replacing them... that I can attest to.

I made two current controlled power supplies from computer supplies. Totally reworked to give controlled voltage and current to test for Rdson.

.....oztules
« Last Edit: September 14, 2015, 06:03:43 AM by oztules »
Flinders Island Australia

clockmanFRA

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I am still working on the 'OzInverter'.

I trust you do not mind a few progression Photos?

That cooling circuit of yours oztules is real nice, threshold setting for start up/off is smart, and the slow fast ramping is good....... Here I am testing it with a 12v battery that is low at 12v, and a heat gun, fan just starting to turn.

I will final set the pots when all installed.

9190-0

My watch/chronometer clean workshop has been invaded. Even my Mrs, remarked, "this is unusual in here to see such stuff all over the place".

9191-1

Here's the Filters and RCD, and the PJ boards and the other 2 fans mounted on the chassis plate.
I have 5 fans, 2 are bang bang on cooling the Transformer, with 2 with ducting on oztules cooling circuit on the PCB's. The 5th is the PJ required one for the PCB to work, its out of the way, but does cool. So if all else fails the PCB's will shut down at excessive temp.

No spiders here, the frogs eat them, but still need to keep things out. I have Stainless steel insect mesh on all air flow inputs and outputs.

9192-2

I now awaiting my last Item/order of the IP67 ON/Off push button latching switch.
« Last Edit: September 24, 2015, 02:59:50 PM by clockmanFRA »
Everything is possible, just give me time.

OzInverter man. Normandy France.
http://www.bryanhorology.com/renewable-energy-creation.php

3 Hugh P's 3.7m Wind T's (12 years) .. 5kW PV on 3 Trackers, (8 yrs) .. 9kW PV AC coupled to OzInverter MINI Grid, back charging AC Coupling to 48v 1300ah battery

Bruce S

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I like the paint job on the name plate too  8)
A kind word often goes unsaid BUT never goes unheard

clockmanFRA

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Credit where credit is due...................

Catchy name eh.?

Besides Bruce, when SMA quiz me over the details "Are you a competent person to install a SMA Inverter", I will say, "Don't know, what is competent?, but your Honour, I got fed up with the bad/faulty SMA Inverter not working properly, so with some encouragement & help from a guy in Australia, I made my own 6kW Inverter, do you want to see mine? ":-*

Its the front door, L to R, the bang bang Fan Temp control meter for the Toroid, with PCB temp sensor meter below. Then the AC output data meter, kW use etc. And the DC Input and kW use etc.



The central hole is for the BIG GREEN latching ON and OFF Button. Gotta have a big button, he he.
Everything is possible, just give me time.

OzInverter man. Normandy France.
http://www.bryanhorology.com/renewable-energy-creation.php

3 Hugh P's 3.7m Wind T's (12 years) .. 5kW PV on 3 Trackers, (8 yrs) .. 9kW PV AC coupled to OzInverter MINI Grid, back charging AC Coupling to 48v 1300ah battery

Bruce S

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Ahh, I knew something was missing  ;D. The Big Button!!
BTW: Not wanting to dredge up or dig into legal issues,,,, BUT how goes the SMA battles?
A kind word often goes unsaid BUT never goes unheard

clockmanFRA

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The case, (60HZ rise, No Warnings in SMA Specifications, Not able to AC Couple and DC couple at the same time, etc),  is now with the European Trading Standards and now with the German Trading Standards Department along with all the correspondence sent, SMA email trails, data files, Engineers reports etc.

Topical at present, I did wander if the SMA software, as Oztules said, is a deliberate policy to lock the SMA Inverter customer to just their products.?  ::)
Everything is possible, just give me time.

OzInverter man. Normandy France.
http://www.bryanhorology.com/renewable-energy-creation.php

3 Hugh P's 3.7m Wind T's (12 years) .. 5kW PV on 3 Trackers, (8 yrs) .. 9kW PV AC coupled to OzInverter MINI Grid, back charging AC Coupling to 48v 1300ah battery

Bruce S

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That would be interesting to pose to the standards engineers.
Should not be too hard to prove, except , if their software is proprietary, then a court order would be needed here in the USA.
That of course would mean they are misleading the customer by NOT telling them upfront about it being a close-looped system not to mention pricey$$$.
Again , hard points to prove. IF proven, then you might want to purchase a few extra of those PJ sets! 'cause everyone else will be looking at buying them too.
A kind word often goes unsaid BUT never goes unheard

oztules

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Gosh.... feeling a bit humble here......


Nice looking build. Should have a powerful and electrically quiet and physically quite inverter that you can have in the same work space if you choose. It will run very peacefully.

If the PJ boards run like mine, you will have trouble free inverting for a long while to come..... I still marvel at just how reliable and stable they have been ( the one driving the house full time)
The ones used for experiment have not been so stable, and I have not found a way to get the charging to work successfully.... and thats a shame, as it would really make these boards  very very useful .  ( not for me, but others ).

Will look forward to hearing how it runs for you in real operating conditions with the grid ties.


I see german manufacturing from trusted and respected manufacturers has been bought under the spot light recently....... and gee I would not be surprised if SMA didn't have a slice of the same cake..... may explain why they have AS4777 accreditation, but tend to  fail their islanding in the field..... it's interesting some  seem to still be running when the other units have shut down from freq errors in excess of .5hz.... gives them the edge in power production in fluffy frequency areas.

I wish my aerosharp chinese things would ignore the .5hz and go 1hz... they would double their outputs on a lot of windy days here when the big mills sway the generator at the power station ( use the term loosely)......

Very nicely done Clockman, and the temporary sacrifices  your missus had made to the cleanliness gods are worthwhile..... keen to see it running.. also keen to see how the grid tie network will work with it, as you are able to program the set points for Vac in them, you should be able to get some reasonable control of the charging from those sources remotely...... interesting to say the least.

I intend to have a fiddle with spare grid ties, and see how we can go about throttling them back internally.... maybe as simple as heating the heat sensors on the heat sinks, and see if that tells the chip to ease up a bit..... maybe it will just error who knows, it will be a start point........ and looking at the maze of electronics in them, finding a start is the hard part.

It may be a Vac controlled fet bank on the input will be easier in the end...... we'll see. The Vac wil only rise if the batts are near full or we are pushing too many kw too fast into them......... from experience.

Well done

.............oztules
Flinders Island Australia

Bruce S

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OZ;
As Clockman begins to wind this Part1 up, what pray tell will be Part2?
Though, if I had the funds available, I'd kinda like to be there when the "official" Big Button gets pushed  8).
A kind word often goes unsaid BUT never goes unheard

Phred

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My 15kW Power Jack Boards, Oz's link.  ........... http://www.ebay.co.uk/itm/121372307145?_trksid=p2057872.m2749.l2649&var=420314377003&ssPageName=STRK%3AMEBIDX%3AIT

Very interesting thread.... Tried to purchase 15kw modules 220v but they are currently unavailable. What is the difference between 10 & 15 kw units? Alternatively can one use 115v version on 220v? Can one fine any technical docs on these beasts other than whats on the Ebay web site?

oztules

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Flinders Island Australia

bcalmed

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I'm too unfamiliar with most of this to know much of anything, but it seems I should start with a core. Are these suitable?

http://www.alphacoredirect.com/contents/en-us/d3_toroidal_cores.html

...and , if so, which is a good choice for an ~8KW build?

Thanks,

Rick

joestue

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depends on the duty cycle of your 8 kw load.

I would try the 5kw toroid, #160.

No load iron loss for those cores is, iirc, 1 watt per kilogram at 1.5T at 60Hz. i can't find the datasheet right now...
My wife says I'm not just a different colored rubik's cube, i am a rubik's knot in a cage.

Neil

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Bcalmed ,

Toroidal Core PN# 170
  I use the Toroidal Core PN# 170 they have and they seemed to work ok.


Neil

bcalmed

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@joestue

What's 1.5T mean? I wasn't kidding about my ignorance....

Mary B

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1.5 Tesla, magnetic force measurement

bcalmed

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So the website has, in the table of specs: "V/TURN @ 60Hz 15kG" - I'm just guessing that 15kG = 1.5T? I think I get that "V/TURN" is volts/turn at 60Hz, but how does the "T" or "kG" apply?

Sorry for the dumb Q's...

joestue

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Volts, Turns, cross sectional area and Hz are all variables in the equation that gets you magnetic flux which is measured in Teslas or kilogauss, or other units. 1.5T is 1.5 Teslas. It would be nice to have 1.5 Teslas in the garage, provided one of them was complete and the other had a good battery pack.
« Last Edit: April 15, 2016, 07:13:22 PM by joestue »
My wife says I'm not just a different colored rubik's cube, i am a rubik's knot in a cage.

oztules

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If you want to run 6kw for long periods, then the 220, and if you just want to run a normal house, then the 170 will probably do all you need.

My home brew ones are much bigger.... but I tend to go over the top too.

.........oztules
Flinders Island Australia

bcalmed

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@joestue

How much would 1.5T add up to in government subsidies?

j/k

bcalmed

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oztules...

I'll go big or go home.

Thanks, your advice is the 5th gospel in my book...

...Amen!

clockmanFRA

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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........   

 
« Last Edit: April 16, 2016, 05:16:26 AM by clockmanFRA »
Everything is possible, just give me time.

OzInverter man. Normandy France.
http://www.bryanhorology.com/renewable-energy-creation.php

3 Hugh P's 3.7m Wind T's (12 years) .. 5kW PV on 3 Trackers, (8 yrs) .. 9kW PV AC coupled to OzInverter MINI Grid, back charging AC Coupling to 48v 1300ah battery

Mary B

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For those wondering who the mystery manufacturer is that he returned. SMA!

bcalmed

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Ever the cheapskate, I was looking at this:

http://www.ebay.com/itm/NEW-2-0KVA-2000VA-230V-to-115V-17-39A-Step-Down-Toroidal-Power-Transformer-/281542186688?hash=item418d38d6c0:g:8Y4AAOSwc3ZUnc-C

I wonder if the green "SCN" is a center tap, could I stuff some primary wire through the middle and parallel the existing primar(ies) and secondary?

It looks like a monster!

Edit: Geez, when I download and zoom the pic showing the wires, they're all labeled AWM 1, but no gauge #'s I can see.
Based on blowing up the image to full size and measuring in my graphics app, they're ~.2 in in diameter - including insulation.
According to a chart I found about AWM wire - they're AWG 8!

« Last Edit: April 29, 2016, 03:01:16 PM by bcalmed »

bcalmed

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or, perhaps, this:

http://www.ebay.com/itm/Toroidal-transformer-2500VA-240V-secondary-153V-primary-with-screen-/191848677023?hash=item2cab127e9f:g:jwYAAOSwiLdV9J2u

Assuming there's center tap or parallel windings on the primary, remove turns on 153V winding and parallel primar(ies)/secondary?

Stuff the middle - I mean that in the nicest possible way....

Edit: just heard back from seller - no center taps. Lots of wires coming out, though - hmmmm....
« Last Edit: April 29, 2016, 02:27:16 PM by bcalmed »