3 Phase converter

[Retired]

Hi,

Many thanks Moose & Richard for your replies.

I'm pleased I asked before jumping in; I've been around the block a few times and know these days things are made down to a price not up to an high standard unless serious money is involved. I note heavy duty Murex TIG welders are available but unfortunately much too big and heavy for my humble needs and they are 3 phase which I don't have laid on any longer. Years ago I installed my own 3 phase 415V for under £120 and ran my Colchester lathe; extractor and bandsaw phase balancing these to the transformer but I eventually downsized so sold the 75kg transformer I had wound to an electrical chum knowing he wouldn't electrocute himself.

I'll accept your sound advice Richard and watch both eBay & Gumtree; I'm not in a hurry to buy a TIG welder; I've got my Pickhill Bantam for general use. Eventually a suitable welder will turn up where I don't need to travel to the end of the planet to collect it?

Kind regards, Colin.

 

[Fazerruss]

Sorry I can't help with the original topic but I'm intrigued you mentioned installing your own 3 phase. Was it a rotary phase converter you built the transformer for?

 

[Retired]

Hi,

Many thanks for asking Fazerruss; before I answer am I allowed to expand on this please on the open forum or is it more appropriate to answer by PM? I'm happy either way and it's something perhaps I'm the only one to have successfully done here in the UK; the method is American and truly unique. Please bear with me Fazerruss and I will reply to you.

Kind regards, Colin.

 

[Fazerruss]

I don't think anyone will mind and I'm sure many others will also be interested. We often go way off course on this forum!

 

[Moose McAlpine]

You can post it here, it's your thread.

Sounds interesting!

 

[Retired]

Hi,

I'm a member of a number of interesting forums and each have their own rules; one vintage radio forum I'm a member of has moderators so keen they behave like traffic wardens on speed and would jump on grammar and spelling mistakes so I'm careful not to offend.

OK so everyone's laid back on here and if you mess with what I'm about to discuss you'll never get off your back again if you make a simple silly mistake. FIRST THE WARNING I'M NOT ENCOURAGING ANYONE TO MESS AROUND WITH MAINS ELECTRICITY IT CAN AND WILL KILL Years ago whilst browsing eBay I came across a guy in America advertising his 3 phase methods and at the time I think I paid around £17 for three very detailed DVD's but now things have moved on and the information can be downloaded so no waiting involved; here's where to start;

http://unique3phase.com/

Douglas Arndt is the creator of "unique3phase" and he's in America so his mains incoming voltage is different to our 240V. The DVD's covered methods of winding a welder; winding a 3 phase transformer and the rotary method; to answer your question Fazerruss no I didn't go the rotary converter way and I'll fast forward a bit to save you wading through all the information. I'm unsure if I'm the only person here in the UK to have succeeded in installing the three phase transformer method; when I got my transformer up and running with my big Startrite Volant 24" bandsaw phase balanced to the transformer Doug asked if it was OK to put a couple of UK guys in touch with me they both wanting to install 3 phase 415V; of course I was happy to help with the usual safety warnings to the two guys; one guy in Wales owned two big farm houses and wanted to install heat pumps running from 3 phase 415V; he had approached his local supply company and was quoted over £17,000 to have the 3 phase connected. I explained I had successfully got my transformer up and running and that I recommend he do likewise; all went quiet for a while then I received an urgent email from him and he explained against my recommendation he had gone the rotary converter route; he had got it up and running and it was doing the job but the noise was keeping the family awake at night and once again he sought my advice; he totally ignored my advice the first time so out of courtesy I simply suggested he build a stone outbuilding in order to isolate the noise; this was the last I heard from him. I wouldn't go the rotary converter route because I believe to power a motor another idler motor of equal size is required so what's the point of running two motors?

I adopted Doug's excellent transformer method. I needed a transformer so I visited our local Schofield's scrapyard in the middle of winter whilst it was snowing way out on the moors; I was perished but I found a big transformer half way up a huge pile of electric motors; I climbed the pile and at great risk I rolled the transformer to the snow covered ground; it took two of us to load this transformer into my small Toyota Aygo; on the way home I was plane spotting.

I stripped all the original windings then I followed the DVD instructions to the letter taking extreme care because I'm not electrically trained and this was highly dangerous. I used 1.5mm and 2.5mm household conduit copper wire bought from Screwfix in 100m rolls. If you have already watched Doug in his video then you'll see just how untidy Doug is his windings looking like a birds nest; because of the length of wire involved Doug had his son run a few blocks for each coil turn but I'm working on my own and this was a problem to resolve; I lay awake in bed and I've solved many problems at around 3am when I can think with clarity in peace; I dreamt up my "shuttle" idea wondering if it would work in doing the coil winding; the following morning keen to try the idea I selected an off cut of plywood and cutting a strip of this I notched both ends; 100m of conduit wire fitted perfectly and I was amazed just how well this method of winding worked; I could pass the shuttle through the lamination window about eight times then spend a bit of time arranging each coil of wire very neatly. First coil is the primary and the most difficult because the primary governs the entire transformer; this was very scary indeed; after a lot of experimentation I finally obtained the 1.5V/turn I needed; now it was easy winding on the secondaries; this is standard transformer winding at it's basic but the unique part is the way the secondaries are wound and connected; I was rewarded with perfect 415V. I promised Doug I would never divulge how the unique part works but it does and for a small price if you are interested please invest in Doug's details; they make fascinating reading even if you don't intend to do any physical work.

Doug now includes me in his details giving me full credit for my shuttle winding method; I ran my transformer for about ten years until I sold my big 3 phase machines; I considered the transformer too dangerous just have in the workshop being idle; if I dropped dead then the transformer would pose a serious accident risk and would prove a liability for Bron to sort out. I sold the transformer to a friend who I believe had already tried to wind and connect a transformer of his own but failed so he was delighted to buy mine having seen it working.

I connected a warning lamp to indicate power was on because I didn't want to leave the transformer switched on it being so quiet. To connect the machines; each machine has to be phase balanced to the transformer using capacitors but once connected each machine can be switched on and off as though mains 3 phase was laid on; I just guessed the size of my 75kg transformer would give 10hp so any number of machines up to the transformers maximum output could be connected; I used to demonstrate by switching on my big bandsaw the whilst the bandsaw was still running switch on the extractor; it was always interesting to see the face of the person watching as I did this.

I used to own a 10hp Transwave static convertor and I grew to dislike this with a passion; starting anything like my Colchester lathe or extractor was a pain; juggling with the controls and if I took a decent cut with the lathe the transwave rattled its head off; starting the extractor was tedious; switch on and wait until the extractor finally groaned its way up to full speed; I can state Doug's transformer method starts machines instantly; the extractor on the transformer used to burst into life. I've gone on at length because I know this is truly unique; I've had electricians criticise when I've told the story but I bet not one of these can connect up such a transformer to supply "any voltage" without Doug's detailed information. PLEASE PLAY SAFE; IF IN ANY DOUBT DON'T DO IT.

I'm a new kid (71) on this forum but I'm into all kinds of things; I even made a bespoke wire wound potentiometer from scratch when a forum member wanted to match the petrol tank sender to the fuel gauge on his extremely expensive vintage car; I like doing things out of the ordinary; hopefully I can add a few pictures.

Kind regards, Colin.

On test under power; keeping well clear not wanting any flash over. This won't take prisoners it will just kill.

The scrap transformer as bought; it cost me £10 paid on weight; I returned the old windings.

Stripped of its windings ready for the fun to begin.

The plywood shuttle I dreamt up; just so easy to use the idea was the difficult one to crack; Doug now uses a shuttle for winding.

Wind a few turns on then tidy each coil up; please note the little clip to prevent the coils unwinding; another little but useful tip of my own.

The shuttle in use; it works a treat and can be done by one person.

Insulation colour is unimportant at least it is to me; I'm hopelessly colour blind. Compare my windings to Doug's?

Here's the completed transformer in all its glory; a great deal of work but highly interesting.

It just doesn't get any better than this; using Doug's excellent method any voltage can be obtained; I wanted 415V so I got 415V; yes I was delighted.

 

[Maker]

Interesting post, am I understanding right that the transformer only has two windings, the 230v mains input on the primary and your 415v output on the secondary? The 120 degree phase shift for the three phases is being handled by your "Balancing capacitors"?

 

[Fazerruss]

Interesting post, am I understanding right that the transformer only has two windings, the 230v mains input on the primary and your 415v output on the secondary? The 120 degree phase shift for the three phases is being handled by your "Balancing capacitors"?

This is what I was also thinking. I would think the only way to get a true 120 phase shift is to have an idler motor.





I've got hold of a transwave static for cheap money and have been experimenting using a pilot motor in conjunction with the lathe I want to run.
It starts up perfectly even on high speed from 0 rpm.

 

[Fazerruss]

The static is just a step transformer with switchable capacitors to balance the phase when the motor is running and what looks like a potential relay to monitor the phase voltage and kick in or out the start cap if the motor stalls.

 

[Fazerruss]

By running this 2 hp motor it also allows me to run the suds pump with no issues. The main lathe motor is two speed but it also runs sweet without the transwave having a fit.

 

[Fazerruss]

Hi,

I'm a member of a number of interesting forums and each have their own rules; one vintage radio forum I'm a member of has moderators so keen they behave like traffic wardens on speed and would jump on grammar and spelling mistakes so I'm careful not to offend.

OK so everyone's laid back on here and if you mess with what I'm about to discuss you'll never get off your back again if you make a simple silly mistake. FIRST THE WARNING I'M NOT ENCOURAGING ANYONE TO MESS AROUND WITH MAINS ELECTRICITY IT CAN AND WILL KILL Years ago whilst browsing eBay I came across a guy in America advertising his 3 phase methods and at the time I think I paid around £17 for three very detailed DVD's but now things have moved on and the information can be downloaded so no waiting involved; here's where to start;

http://unique3phase.com/

Douglas Arndt is the creator of "unique3phase" and he's in America so his mains incoming voltage is different to our 240V. The DVD's covered methods of winding a welder; winding a 3 phase transformer and the rotary method; to answer your question Fazerruss no I didn't go the rotary converter way and I'll fast forward a bit to save you wading through all the information. I'm unsure if I'm the only person here in the UK to have succeeded in installing the three phase transformer method; when I got my transformer up and running with my big Startrite Volant 24" bandsaw phase balanced to the transformer Doug asked if it was OK to put a couple of UK guys in touch with me they both wanting to install 3 phase 415V; of course I was happy to help with the usual safety warnings to the two guys; one guy in Wales owned two big farm houses and wanted to install heat pumps running from 3 phase 415V; he had approached his local supply company and was quoted over £17,000 to have the 3 phase connected. I explained I had successfully got my transformer up and running and that I recommend he do likewise; all went quiet for a while then I received an urgent email from him and he explained against my recommendation he had gone the rotary converter route; he had got it up and running and it was doing the job but the noise was keeping the family awake at night and once again he sought my advice; he totally ignored my advice the first time so out of courtesy I simply suggested he build a stone outbuilding in order to isolate the noise; this was the last I heard from him. I wouldn't go the rotary converter route because I believe to power a motor another idler motor of equal size is required so what's the point of running two motors?

I adopted Doug's excellent transformer method. I needed a transformer so I visited our local Schofield's scrapyard in the middle of winter whilst it was snowing way out on the moors; I was perished but I found a big transformer half way up a huge pile of electric motors; I climbed the pile and at great risk I rolled the transformer to the snow covered ground; it took two of us to load this transformer into my small Toyota Aygo; on the way home I was plane spotting.

I stripped all the original windings then I followed the DVD instructions to the letter taking extreme care because I'm not electrically trained and this was highly dangerous. I used 1.5mm and 2.5mm household conduit copper wire bought from Screwfix in 100m rolls. If you have already watched Doug in his video then you'll see just how untidy Doug is his windings looking like a birds nest; because of the length of wire involved Doug had his son run a few blocks for each coil turn but I'm working on my own and this was a problem to resolve; I lay awake in bed and I've solved many problems at around 3am when I can think with clarity in peace; I dreamt up my "shuttle" idea wondering if it would work in doing the coil winding; the following morning keen to try the idea I selected an off cut of plywood and cutting a strip of this I notched both ends; 100m of conduit wire fitted perfectly and I was amazed just how well this method of winding worked; I could pass the shuttle through the lamination window about eight times then spend a bit of time arranging each coil of wire very neatly. First coil is the primary and the most difficult because the primary governs the entire transformer; this was very scary indeed; after a lot of experimentation I finally obtained the 1.5V/turn I needed; now it was easy winding on the secondaries; this is standard transformer winding at it's basic but the unique part is the way the secondaries are wound and connected; I was rewarded with perfect 415V. I promised Doug I would never divulge how the unique part works but it does and for a small price if you are interested please invest in Doug's details; they make fascinating reading even if you don't intend to do any physical work.

Doug now includes me in his details giving me full credit for my shuttle winding method; I ran my transformer for about ten years until I sold my big 3 phase machines; I considered the transformer too dangerous just have in the workshop being idle; if I dropped dead then the transformer would pose a serious accident risk and would prove a liability for Bron to sort out. I sold the transformer to a friend who I believe had already tried to wind and connect a transformer of his own but failed so he was delighted to buy mine having seen it working.

I connected a warning lamp to indicate power was on because I didn't want to leave the transformer switched on it being so quiet. To connect the machines; each machine has to be phase balanced to the transformer using capacitors but once connected each machine can be switched on and off as though mains 3 phase was laid on; I just guessed the size of my 75kg transformer would give 10hp so any number of machines up to the transformers maximum output could be connected; I used to demonstrate by switching on my big bandsaw the whilst the bandsaw was still running switch on the extractor; it was always interesting to see the face of the person watching as I did this.

I used to own a 10hp Transwave static convertor and I grew to dislike this with a passion; starting anything like my Colchester lathe or extractor was a pain; juggling with the controls and if I took a decent cut with the lathe the transwave rattled its head off; starting the extractor was tedious; switch on and wait until the extractor finally groaned its way up to full speed; I can state Doug's transformer method starts machines instantly; the extractor on the transformer used to burst into life. I've gone on at length because I know this is truly unique; I've had electricians criticise when I've told the story but I bet not one of these can connect up such a transformer to supply "any voltage" without Doug's detailed information. PLEASE PLAY SAFE; IF IN ANY DOUBT DON'T DO IT.

I'm a new kid (71) on this forum but I'm into all kinds of things; I even made a bespoke wire wound potentiometer from scratch when a forum member wanted to match the petrol tank sender to the fuel gauge on his extremely expensive vintage car; I like doing things out of the ordinary; hopefully I can add a few pictures.

Kind regards, Colin.

View attachment 186382

On test under power; keeping well clear not wanting any flash over. This won't take prisoners it will just kill.

View attachment 186383

The scrap transformer as bought; it cost me £10 paid on weight; I returned the old windings.

View attachment 186384

Stripped of its windings ready for the fun to begin.

View attachment 186385

The plywood shuttle I dreamt up; just so easy to use the idea was the difficult one to crack; Doug now uses a shuttle for winding.

View attachment 186386

Wind a few turns on then tidy each coil up; please note the little clip to prevent the coils unwinding; another little but useful tip of my own.

View attachment 186387

The shuttle in use; it works a treat and can be done by one person.

View attachment 186388

Insulation colour is unimportant at least it is to me; I'm hopelessly colour blind. Compare my windings to Doug's?

View attachment 186391

Here's the completed transformer in all its glory; a great deal of work but highly interesting.

View attachment 186392

It just doesn't get any better than this; using Doug's excellent method any voltage can be obtained; I wanted 415V so I got 415V; yes I was delighted.

What was the turns ratio on your transformer and what size wire did you use on the primary and secondary?

 

[Retired]

Hi,

Thanks for asking; no the transformer has the usual single primary winding but more than one secondary windings that need connecting as per Doug's instructions in order to gain the output voltage required; the capacitors only phase balance the motor to the transformer; winding and connecting the secondary windings is the "unique" part. The transformer is wound 3 phase and it's the winding connections which give the third phase.

If it was just a case of connecting 3 phase directly to single phase supply using capacitors then this is different and it's another method I've used but is very common. I used to own a Startrite combination woodworking machine fitted with four motors; the three main motors were each 3 phase 3hp but being modern motors had the six wires so could be connected in "Delta" to run on the 240V supply; all three motors were identical so I rigged it to run with just one start and one run capacitor; each motor could be switched in or out by a master rotary switch ensuring only one motor was powered at a single time; this was another machine I ran for about ten years; I totally rebuilt it when I bought it in scrap condition; I dumped the thicknesser power feed and installed chain drive power feed via a single phase motor. I also run my Fully restored lathes through one VFD both lathes having identical motors; each lathe is switched so that only one lathe can be run at a time; as I say I get up to all sorts of things and I was honoured with top restoration award by The British Vintage Wireless Society in 2009 for my AVO Wave Winder restoration.

Kind regards, Colin.

Here's my restored Startrite showing the start & run capacitors just below the control panel. I'm using it as a support whilst I route 600' of moulding. 3 phase but I ran it for ten years from 240V single phase.

Heavily modified to chain drive for thicknessing. Oak being thicknessed for the new desk I made.

Here's an Ekco T311 TV/Radio I restored and did the restoration in real time on a forum doing it in two sections the cabinet and the chassis I'd restored over 100 vintage radios but this was the only TV I ever restored; I'm a mechanical engineer so entirely self taught in many things I do.

https://www.vintage-radio.net/forum/showthread.php?t=62371

Yes the same Ekco but as bought in need of a bit of TLC.

My Lorch Schmidt very very rare engineering lathe as bought after it had been stored in a scrapyard for over twenty years.

I just love tinkering around; the Lorch after a bit of magic; I've since modified it to Poly V drive 3 phase through a VFD all power feed it's a wonderful lathe to own.

I recently bought two vintage coach lamps and needed three pairs of reflectors so i made my own by learning metal spinning doing these on my fully restored and highly modified Graduate wood turning lathe.

I even do welding; I gave our bungalow exterior a comprehensive makeover; the steel work was all mine as was the garage doors and cladding; the paint is very expensive American Benjamin Moore; I never accept second best and don't understand compromise.

My Startrite Volant undergoing full restoration. This was powered by my 3 phase transformer.

The capacitor bank used to phase balance to the transformer.

Oh dear I do ramble on with just the slightest encouragement. I'm not an expert or a know it all I just enjoy doing different things leaving my comfort zone. Good job this isn't the vintage radio forum or I'd be locked up for wandering slightly "off topic".

 

[daleyd]

Ramble away

 

[Retired]

Hi,

Thanks Fazerruss for your input and pictures. It looks like you too have found a few shortcomings using a Transwave converter. Seeing the Transwave pictures brings back lots of memories. When I first bought my 10hp Transwave I was so disappointed with it's starting power or lack of starting power I crated it up and sent it back to Transwave for testing; I had bought mine as new but second hand; it was tested by Transwave who declared it was working fine; over the next few years I grew to really dislike this Transwave mostly because I was running assorted 3 phase machines from the one Transwave it then meant lots of knob twiddling and worst of all the poor starting power; I'm sure had I only ever used my Transwave on one machine I might have accepted it but I grew very weary of it indeed so I let it go with one of my big lathes.

I'd like to make it clear I'm not a sparky; I'm a mechanical engineer who likes to try lots of things which grab my interest; in 1964 as an apprentice mechanical engineer I attended a six month long training course at Crigglestone Colliery Training Centre; I got so far in front of my fellow apprentices I completed the course in record time; this meant I was on my own but I'm nosy and want to learn so I drifted over to the apprentice electricians and was allowed to join in; I was taught how to connect up big industrial 3 phase motors but at dinner time I was quietly allowed home on full pay so this is the only electrical training I've ever received.

Regarding capacitor being used for phase changing yes they do but the point of this unique3phase isn't focussed on the capacitors it's focussed on how to wind a transformer to put out 3 phase the third phase derived from the transformer secondary windings and how these windings are connected so it's two wires in from single phase supply and three wires out from the transformer windings; well you might think this insignificant but actually the transformer connected like this supplies 3 phase on full 3 phase power up to the transformers top output; now we've wound the transformer and obtained the 3 phase output voltage then yes now capacitors phase balance each motor to the transformer; it's extremely interesting watching the voltage on the 3rd phase as capacitors are added or taken away; I just phase balanced at motor idle but once the motor was balanced then it behaved just as if connected directly to 3 phase.

What is significant is that this is a way of obtaining full power without messing around with converters or adding additional idler motors; no more converter rattling; no more juggling with switches; just switch on the transformer and switch on the machines; yes machines because any number of machines can be run all at the same time up to the transformer maximum output; try doing this with a static converter?

All the details regarding how to get one of these transformers up and running are included in great detail in Doug's information including wire gauges; I used 1.5mm and 2.5mm single core conduit wire but it depends on the transformer laminations being used; by the way if a donor transformer cannot be obtained Doug explains how to use an electric motor stator; a 30 hp motor stator would make a very useful 3 phase supply but everything is explained by Doug.

Good question Fazerruss regarding turns ratio and this is the very first thing to sort out because its so important. There is no standard as to turns ratio for anyone doing this at home because there's no way of doing the testing however by trial and error following Doug's instructions I eventually achieved 1.5V/turn on the primary which was perfect; more or less turns of wire changed the current quite a bit; my big transformer idled at 0.8A which is very impressive indeed wound at 1.5V/turn but it took quite a bit of playing around with turns to obtain this. Once the primary turns ratio is known then the secondaries are very easy to work out; take my 1.5/turn; this means for every turn of the wire on the primary it puts out 1.5V; so if as I did I wanted 415V all I had to do was to divide 415 by 1.5 which gives 277 turns for the primary; this is for normal transformer winding but this isn't normal transformer winding it's unique hence please buy the details from Doug?

I've wound many vintage radio transformers; coils and chokes etc and even wound my own transformers for power supplies which I needed; I can highly recommend a book giving very basic transformer winding instructions that got me off to a flying start because I could understand the few pages covering the subject; Wireless Coils, Chokes and Transformers by F.J. CAMM.

Thanks daleyd; I've been grafting all my life so far with no let up in sight; I'm built like a six foot tall stick insect and never want to give up grafting; too many retire then drop dead the day after through boredom.

Now back to the plot; I'm interested in a Stamos AC/DC TIG s-AC200P basic and it's on offer at £450 or make an offer; it's complete with foot control; any good please?

Kind regards, Colin.

My AVO hand winder.

Transformer laminations; these come in a few patterns.

A very special winder; this is the AVO wave winder I fully restored from scrap and won the award for. I found a new way to cut 45 cast iron gears on my lathe that had never previously been done.

Here's another way to obtain 3 phase using Doug's method.

It's surprising the amount of material used in transformers; this is a small output transformer for a vintage radio.

 

[Fazerruss]

So does this "unique way" of winding the transformer produce 3 outputs all with the correct 120 degrees phase shift?
From what I've read elsewhere if you have two secondaries wound in opposite directions you will get 180 degree phase shift. So is it using this principle somehow?
I'm even more intrigued now as this would be a much better substitute 3 phase supply than using an RPC.

Ps

Just has a look at Stamos TIGs. They look like the generic Chinese WSE welders rebadged. They are known to go pop at any time. If you go down this route make sure it has a rock solid warranty that includes shipping etc and from a uk dealer.

 

[Retired]

Hi,

Thanks for asking Fazerruss; the easiest answer is to buy Doug's information then hopefully it will explain better than I can; my 3 phase transformer was brilliant running my machines without the slightest problem and it was and possibly still is very reliable. The only slight problem I encountered was tripping of the mcb at times no doubt due to surge; if the mcb tripped I could reset it immediately and everything was fine. I still get the odd tripping when I power up my Pickhill Bantam welder even though it's running from a 32A "C" type breaker.

Kind regards, Colin.

 

[Fazerruss]

I'm too tight to buy any information, I'm from Yorkshire!

Beautiful restorations by the way.

Here is one of mine

From this



To this

 

[Wozzaaah]

I will split this thread into two separate ones later.

 

[Pete.]

I will split this thread into two separate ones later.

Primary and secondary?

 

[Wozzaaah]

Thread now split.