10HP 3phase 415V for £120.


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24 Jun 2012
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Fenay Bridge. Huddersfield.

I was delighted to read Bob's (9fingers) thread covering “Use of induction motors in the home workshop”. This is the best write up on the subject I've seen and top marks to Bob for sharing it as it is most informative and highly useful.


I hope my story of how I added 3 phase 415V at 10HP into my garage might be of use as many members would like to install 3 phase but are put off by the high costs involved. Just after installing my system a guy in Wales contacted me for advice as he wanted to install 3 phase into his two farmhouses to run heat pumps; he needed around 30HP. The local electricity supply company quoted him over £17,000 to run the 3 phase in.

Having just installed my own 3 phase I suggested he go the transformer route but he decided to go the rotary converter route instead and all went quiet for a while; I then received an email from him once again asking for advice; he had built and installed the rotary converter which was working well but the family couldn't sleep at night because of the amount of noise it was making. Had he gone the transformer route the transformer would be virtually silent. I suggested he build a remote stone building to match his farmhouses and install the converter running a power cable to the farmhouses; I've not heard from him since but wish him the best of luck.

As a member of The British Vintage Wireless Society I submitted the story and had it Published so rather than start over I'll simply add the original story as below. I must stress that I am not trained in electrics and what I know I've picked up over the years but I found installing my 3 phase to be quite straightforward but for anyone with doubts please don't consider trying it as it can be highly dangerous and could prove lethal.
Being fed up of bumping into machinery in my garage I decided to remedy the situation just before Christmas 2008 by selling four of my large industrial machines together with my Transwave 7.5KW 3 phase 415V static converter. I was sorry to part with all this gear but the space would be more useful.

I still retained my dust extractor and my lovely wife Bronwyn bought me a huge Startrite Volant 24” band-saw for Christmas both these on 415V. My initial intention was to power these directly from the UK 240V supply using start and run capacitors; I have previous experience of this as I converted my Startrite combination woodworker about ten years ago. To run on three phase 240V is easy enough but requires the motors to be reconnected in “Delta” by doing this the machines run but on reduced power and are unbalanced giving similar performance to using a static converter.
On 6th. December 2008 whilst browsing eBay I came across three DVD’s for sale from a company called “Unique3phase” and these looked excellent value with a running time of six hours. The disc’s covered all aspects of installing high voltage 3 phase at little cost which immediately appealed to me; I viewed the sample video clips and ordered the disc’s paying by PayPal. A week or so later the discs arrived and I couldn’t believe how good they were; they covered rotary, stator and transformer methods together with how to make a welder. I was amazed at how simple it all was. I ran the discs on TV taking a few notes then visited a number of contacts where I obtained a scrap 5.5KW motor to act as a donor giving me the laminations (stator) which would be the core of my new transformer. I stripped the motor and split the casing removing the stator; I then had a bit of a struggle removing the windings but ended up with a good clean set of bare laminations. At this point I thought that I would be smart and wound on the primary as one coil using the entire stator in similar style to a “Toroid”.  I felt very proud at achieving this with so little difficulty until I plugged it into the mains and promptly tripped the 30A breaker?

The creator of Unique3phase Douglas Arndt in America was absolutely brilliant when I e-mailed him and over the next four weeks he was unstinting in his generous help and guidance. Doug had tried this way of winding mentioning it on the disc but saying it hadn’t worked without giving a reason why; apparently the problem was the type of core; the laminations are stamped out of steel whereas a Toroid core is wound from one continuous strip and this is also twisted? I rewound as per Doug’s instructions and after tripping the breaker a few more times finally could power up to take instrument readings. Each time I tripped the breaker it took the central heating out as well. The best I could achieve with this stator was 0.8V/Turn which would have worked by using more wire on the secondaries but by now I was well and truly hooked on this project so decided to follow Doug’s example and obtain a much larger stator; I would now try to obtain a 25HP motor to strip?

14 January 2009 I had tried my contacts to obtain a larger motor without success so decided to visit our local scrap yard high on the moors. As I searched the yard at 9.30 am I was blasted with horizontal rain due to the wind and it was absolutely freezing. There was a huge pile of stators but these had been burned to remove the copper wire; I also saw two small rough looking 3 phase transformers on the same pile but rejected them. I then walked across to a very high pile of scrap motors; I saw two suitable motors but the casings were cast iron and I would have to call the crane over to pull one out; I then noticed another 3 phase transformer near the top of the pile but it had no markings on it so was rejected. At this point I was soaked and frozen so went back to the car to decide what to do. I had taken a good selection of tools along in a plastic bucket but had left my gloves at home. The bucket had started to fill with freezing water and as I sat there I wondered what type of fool I was to be out on a day like this? I could go home and forget the whole project; I could get the big motor craned out and strip it then it suddenly struck me that the large transformer might be just the job as I could rewind it to my own specification? I thought to myself don’t be such a wimp and get out there to do what you came to do!! I took along a tea towel from the car and climbed the pile of motors to the transformer; using the towel to prevent cutting my hands I eased out the transformer and very gently slid it down the pile all the time worried in case I got buried under motors which was a real possibility. As it sat in the icy mud I inspected it and then went to ask the price to be quoted a very fair £10. I rolled it over and over to a spot where I could reach it with the car and it took two of us all our strength to lift it into the car; it was extremely heavy. The car being a new Toyota Aygo was plane spotting all the way home and the traffic lights all at red and the road humps added to the stress. I removed the transformer on my own from the car using a short scaffolding plank taking a week to start talking normally again.

Scrap transformer as bought..JPG

I couldn’t use the transformer as it was because it was soaking wet so chopped through the coils totally removing them leaving the laminations and three fibreglass formers intact. I wiped it as dry as possible then let a fan heater warm it up for a couple of hours.

Coil stripping.JPG

I followed the instructions on the discs and wound the primary coils using 2.5mm stranded copper insulated conduit wire; Doug stresses that it pays to get this part right so I spent some time experimenting with the number of turns and found that I could achieve 1.8V/Turn but with increased idle amps so I added turns bringing it down to 1.5V/Turn and now the amps were very impressive giving me 0.8A at idle.
I didn't know a transformer could be powered up with only the primary winding added but this is how the volts/turn is achieved; with the primary winding added then a length of 2.5mm insulated wire was wrapped twice around the coil leaving both ends exposed and easy to get at as a voltage reading would be taken. Using a digital mutimeter set at the 10V range the number of primary turns could be experimented with.

This was perfect for me and I then wound on the secondary coils using 1.5mm Stranded copper insulated conduit wire. With a bit more experimenting with the number of turns I obtained perfect voltage readings and had myself a fully working single phase transformer wound as per Doug’s instructions that would now give full power at 415V with the use of capacitors. Each machine would be switched and phase balanced to the transformer. I bought a selection of capacitors shipping them in from America from a company called Surplus Center and they worked out cheaper than buying new in the UK even with the high shipping costs.

Only two “legs” of the transformer are used and it is this and the way the coils are connected that is unique. Simply obtaining a scrap 3 phase transformer will not give 3 phase at home from the standard 240V supply.
Doug has indeed come up with something “unique” in his methods of supplying 3 phase power;  with the DVD’s explaining in great detail each stage it is hard to go wrong although I managed it a couple of times but Doug was very prompt at helping me out. I tried his stator method which avoids the problem of trying to find a 3 phase transformer and I also tried his transformer method both of which work. The methods are incredibly versatile as you can control fully the voltage you need for the 3 phase whether it be 240V or 680V in my case I wanted 415V which is exactly what I now have. Due to copyright I haven’t gone into great detail regarding how the 3 phase is achieved indeed it wouldn’t be fair to Doug. In basic terms though to use the stator method you wind both primaries and secondaries from scratch onto the bare laminations (covered with insulation) but if the transformer method is used and a suitable transformer is found this saves a lot of work and wire. Both methods involve winding as a single phase transformer but Doug’s unique method then converts them to full 3 phase. I’ve wound mains and output transformers in the past for wireless work but never seen anything like this. I spent a month on this project but could have completed it much quicker had I not been hampered by doing it in the middle of a Yorkshire winter. At times the project has been hernia and pneumonia inducing requiring real will power to continue but what a learning curve it turned out to be; the final test of my stamina was to locate the finished transformer in a safe place in the garage to this end I welded up a pair of very heavy duty brackets fixing them near the ceiling in the garage with large anchor bolts. Getting the transformer into position almost put my light out permanently. It was pure pleasure to run a ring circuit to the machines and see them burst into life at a touch of a button; balancing the phases to each motor has to be tried to be believed; by putting capacitors in and taking capacitors out it was just incredible to watch the volts and amps change and was so easy; this system puts the static converter to shame; my dust extractor used to take ages to wind up with the static converter but now with the transformer it’s immediate. Running costs are low compared to a rotary converter. Briefly to run a 10HP motor through a rotary you would in fact be running something like 30HP due to the required idler motor; my transformer is brilliant and idles at 0.8A it is also silent in operation. For safety and to let me know it is switched on I fitted a panel mains indicator lamp.

I hope Doug doesn’t mind me mentioning but when I first saw his DVD’s I thought he was producing bird’s nests as the wiring was all over the place also his method of winding the wire is totally different to mine. Doug lets his son run the wire out using a pulley system taking the two of them to wind. I work on my own and winding the wire was a real problem I faced; I lay awake most of one night in bed trying to think up a solution that would work for me. I came up with my “shuttle” idea which is so simple but very effective in use.

Important shuttle..JPG
Using wire shuttle..JPG

I used an off cut of 3/8” plywood 44” long by 3” wide, at each end I cut out a rectangle leaving a pair of horns 1” long by ¼” wide this would prevent the wire slipping off. This was sanded smooth as it would be handled a lot. I found I could get a full 100m coil of 2.5mm wire on the shuttle taking care to wind the wire on neatly by turning the shuttle end over end so that no twists were introduced then with a little practice I could wind 2 turns per minute onto the transformer. I would wind on about 7 turns; place the shuttle down freeing both my hands then I could gently arrange the wire neratly pulling it tightly before clamping the loose end with a spring clip to prevent it from springing loose. One point is that I would now put a first aid sticky plaster around my finger to pull the wire tight with as I opened up a wound that really made me jump when I washed my hands in soapy water. In the stator method I made a pair of flanges out of plywood and these were mounted securely allowing neat winding.

Winding completed..JPG

Costs; in all I had change out of £120 with my transformer, this included the capacitors, brand new wire and scrap transformer. The only downside was our UK climate some days it didn’t get light at all and as I tried to take pictures of work in progress the flash would wash the picture out whereas a normal picture came out dull but then I wasn’t considering writing this up as an article until fellow British Vintage Wireless Society (BVWS) member Martin Scobie suggested it would be of great benefit to other members wishing to install 3 phase into their workshops. With 7.5HP static converters costing in the region of £600 new and rotary converters costing in the region of £1,000 new this transformer method is an absolute bargain for those willing to put the time and effort in. I found this project to be addictive and very interesting.

Transformer powered up on test..JPG
Perfect 415V..JPG

I used to own a big Colchester Triumph engineering lathe fitted with a 5HP main motor and powered this through a Transwave 7.5HP static converter. Right from the start I was disappointed with this converter; yes it did the job but what a lot of hassle; I actually thought the converter to be faulty so contacted Transwave then returned the converter for checking and servicing costing £30. There was nothing wrong with the converter and I was told the third phase would give a low votage reading until the machine was up to speed; starting power was very poor and even at speed if I tried to use the lathe as it was designed for taking a heavy roughing cut the converter used to rattle its head off; if I weanted to power another machine through it then I had to keep ajusting the main selector; I let the converter go with the lathe when I sold the lathe.

Doug's unique 3 phase is totally different in use and provides full power all the time; starting my home made 3 phase dust extractor with the Transwave converter used to take ages to run it up to speed as of course it being a fan motor it starts under load. Using Doug's transformer method the dust extractor really bursts into life. Not only this but once the individual machines are phase balanced to the transformer then they can be switched on and off just as if normal 3 phase was installed; it dosn't even matter if one machine is already running as any number of machines can be switched on and off up to transformers maximum output and even this can be greatly increased by submerging the transformer in oil; the transformer doesn't mind. I can reveal that the thrd phase is supplied from a 600V winding on my transformer and this together with Doug's unique method gives the full power.

Finished transformer..JPG
Not recommended by H&S..JPG

Safety is a major consideration on this project and I only offer my experience having completed both stator and transformer methods successfully. Anyone wishing to have a go does so entirely at their own risk as dangerous voltages are ever present together with large fully charged capacitors. Capacitors should each be fitted with a discharge 2W resistor and the resistor should not be fully trusted; it pays to double check by bridging the capacitor terminals (power turned off) with an insulated handled screwdriver; take extreme care when handling capacitors. Work slowly and unplug before handling anything; my transformer is silent just waiting to put me on my back and the high voltage will kill without warning. If in any doubt whatsoever do not attempt this project.

Transformer installed and working..JPG

I can’t thank or praise Douglas Arndt enough for creating Unique3phase and for all his help during the project. 
The DVD’s cost me a total $25.52 USD at the time this converted into £17.76GBP 
By Post: Douglas Arndt. 10671 N.Idaho RD, Post Falls, Idaho. 83854 USA.
By Internet:
http://members.ebay.com/ws/eBayISAPI.dl ... ique3phase
Wire in the UK; Screwfix.com

Kind regards, Col.


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Dude, you've got b*lls. Big brass ones.

who runs a 10 hp RPC at home made from a surplus idler, a few capacitors, fused knife switch, and a 1/3 hp pony motor (total cost maybe $100), but only needs 240V 3ph.
ProShop":1r9ssib4 said:
Fantastic, really interesting.
thanks for posting

=D> =D> =D>
=D> =D> =D>

Yes this technique is interesting. I've bought the book and DVD package in order to expand my knowledge BUT there are drawbacks.

In essence you need to make the special transformer and distribute the output to each machine. You will need to to use special connectors to avoid confusion with traditional 3 phase - especially in a professional or multi user shop.
I've no idea about getting Part P approval for such a set up (not that I'm a fan of Part P - don't get me started!)
Also each machine needs a custom 'tuned' modification to match it's motor to the special supply.
Having done this it will work as the OP describes.

Good electrical skills will be necessary to both make the hardware and tune it to the machines safely.

In contrast the Transwave converter is a self contained plug and play unit which necessarily has to be a compromise solution to suit machines within its power range and as such will SOMETIMES not perform as well as the customised solution described.

Bear in mind that any new machine introduced into a workshop will have to be modified and anything you want to sell will have to be converted back to conventional 3 phase. It may be possible to build a self contained box for each machine to make this easier. I'll have to have a think about this.

The cost quoted by the OP relies heavily on being able to pick up a suitable transformer core cheaply. You may have to search for sometime to find one at all but when you do it is likely to be fairly cheap.

I think I have enough bits around to try a low power one as an experiment - damn that's another thing on my round-2-it list.

Can I first say "Thank you" to Col? This is a candidly honest, warnings built in, 'Gawd-am-I-crazy?' account, but one that is heartening in that it shows it IS possible to make a working three phase installation, reasonably cheaply.

Secondly.......Bob? Hear you loud and clear. Electrical energy above 0.45amp (or is it 0.28?) will kill in one fiftieth of a second - faster than you can blink, so this is NOT "something for the weekend" by 'Have-a-go-Henry'.

Like Col, I too have purchased the DVD's and came to the realisation that this was something to be approached with great care, after studious research. To that end, I went through Jim Cox's two archetypal wee books (see below), experiencing great confusion, but the one that REALLY made a difference and made greater sense of the Arndt idea was Graham Astbury's "Three Phase Conversion", Workshop Practice Series, No 47. Try Tee Publishing or RDG for a copy. I contend, that it is possible, with METICULOUS planning, to create a SAFE installation, and sorry Col, yours just isn't. The exposed nature of your rig, with conductive metals so close, just tightens several of my visceral and reproductive twitch muscles SO strongly......

Hypocritically, after that comment, I still think Col is on to something good, but one that has, has, has, to be planned, carefully tested AND ENCLOSED!!!! Will I be attempting one? Yes. Slowly, with great trepidation and all possible precautions.

I spoke to Wallace (of restored Wadkin fame) at the weekend and he too had a Transwave set. He too had problems with it in use. I believe they (Transwaves) are good within their stated limits, but that those same limits may be restrictive in practice? I state that in total ignorance of Transwave and stand to be forceably corrected by Transwave themselves or pleased and satisfied customers. My problem is, I find them too expensive and (anecdotally) possibly limited in backyard/amateur use.

Sam, concious he may just have kicked the collective nests of several wasp species.....

Jim Cox, "Electric Motors" and "Electric motors in the workshop", Nos 16 and 24 respectively in the Workshop Practice Series.

Thanks Kirk; yes it's amazing what can be done with little money but a lot of determination.

I'm pleased you find it so interesting ProShop and you are most welcome.

It's good to learn that you've bought the book and DVD's Bob. I do hope you have a go at Doug's “Unique3phase” transformer method then like me you can compare it against a static converter. You've raised some very good points Bob but a number I've already covered. Yes it requires the transformer to be wound as per Doug's instructions and yes each machine needs to be phase balanced to the transformer. In a home workshop why would it make any difference to use special connectors to avoid confusion with standard 3 phase? Just one look at the transformer would be warning enough that something was different and in a home workshop this method would be installed because 3 phase isn't laid on in the first place.

Regarding industrial use of this method I confess I haven't a clue in fact “Part P approval” is something I've never heard of. To make it even more interesting for me I'm hopelessly colour blind and it is this that made me go into mechanical engineering as a 15 year old apprentice mechanical engineer firstly at the Grange Ash Colliery then I transferred to The Caphouse Colliery which is now the National Mining Museum. I was working underground aged 15 carrying the engineers tool bags.I have no background electrical training and have already stated I'm self taught regarding my knowledge of electrical work. I think you are possibly light years ahead of me Bob when it comes to electrics.

Good electrical skills are needed? Perhaps if I had electrical background training I might have run away rather than attempt this project as I found it both scary but exhilarating at the same time. I don't frighten easily but I have self survival well and truly built in and believe me I watched the DVD many times before I felt confident enough to make a start.

A very good point about the static converter being a compromise Bob and I fully agree with this because I found it to be true using the static converter over a number of years. I'm not calling static converters names and in particular I don't wish to offend when it comes to using a Transwave converter; all I can do is compare both methods fairly through my own experiences of using the two.

The static converter is not as convenient as indicated; each machine needs connecting to it so is it a case of unplugging one machine and plugging another machine in then playing around with the controls or would it be better as I did and run a circuit with each machine in parallel allowing a single connection at the converter? Doing it this way with the circuit I still had to juggle with the controls of the converter. The 7.5HP static converter I had was big and heavy so it would have been extremely difficult to move it from machine to machine hence I made it stationary and ran the circuit to it. It was whilst doing this I found the 3rd phase to be way down on voltage; I expected to see a reading of 415V? I also mentioned that my big engineering lathe disliked the static converter if I wanted to use the lathe as it was designed to be used for; was I expected to keep playing around with the controls between light and heavy cuts? I found the static converter to be inconvenient for my needs and this is why I parted company with it. As I say; I mean no offence to Transwave or indeed any static converter manufacturer ; the converter worked and generally did the job but with problems and it wasn't cheap either.

I'm not trying to sell Doug's unique3phase as my only contact with Doug is as a highly satisfied customer who bought the set of DVD's. I am however trying to pass the information on to interested parties who would like to have a go at installing a similer 3 phase supply at little cost. I've never said it would be easy in fact I found it to be extremely difficult but by taking my time and certainly not taking any risks I followed Doug's instructions to the letter and as a non trained electrical person I have proof that both the Stator and transformer methods not only work but work well.

C'mon Bob; please get stuck in and make your own transformer following to the letter Doug's instructions then report back. I'm sure you will find as I have that the static converter won't only sometimes not perform as my transformer but it won't perform at any time like my transformer. I don't need to try to convince you Bob so please have a go and prove it to yourself. A very simple test would be as Doug shows so well on his DVD is to power up a compressor with the static converter then power up with the transformer; I reckon no contest. The transformer once phase balanced to the machine gives full power from the push of a button.

One thing I did different to Doug is that I used a seperate heavy duty "push to make" start button to bring the start capacitor online; to start my machines I press both buttons together and the machine bursts into life then I simply let go of the buttons; the run capacitor remains online but the start capacitor drops offline; I didn't know enough about wiring relays as shown by Doug but I did grasp what was needed hence the second button. I don't even give it a thought now; I switch on the transformer which by the way is so big it occassionally trips the 30A breaker due to surge at power up; this is not often and I would like to investigate if it would be possible to add a soft start but I always have plenty of other projects on the go; then I press both buttons on the machine and get to work. If you go ahead Bob I think you will be very surprised by how good Unique3phase actually is and good luck.

Many thanks Sam for your post and I'll hold my hand up high; yes my transformer would scare even the hardest health and safety inspector as it is with the open connections one being at 600V with a 30A kick but I thought long and hard where to position the transformer not only for my own personal safety but for any visitors especially inquisitive children. It was a major problem getting the big lump of metal up against the garage ceiling working on my own which alone would have scrared the H&S lot but I succeeded. I never ever leave the transformer powered up on its own; I'm always very nearby and when visitors pop in to see me it is switched off for safety unless I'm demonstrating it then the visitor is verbally warned of the danger it poses. In this position the transformer is always dry with no chance of water coming into contact from a wet car; it is also open to allow for full ventilation but I take your point most seriously Sam and I think it time I rigged up a perspex screen just to be sure. It is fitted with a heavy duty earth lead and protected by a 30A breaker. I never touch it whilst it is powered and ensure I never bump it whilst holding anything or allow anything to drop upon it. In fact I switch it on; use the machine then immediately switch it back off. This transformer is not a toy and is just waiting to kill as it was whilst I was constructing it.

No need to apologize Sam as you are right and I respect straight talking of a constructive nature which yours clearly is. Thanks also Sam for the additional information; I'm always willing to learn.

Have you actually had time to view the DVD's Sam as I would like to hear both your's and Bob's thoughts having watched Doug in action powering his big compressor up; I found it fascinating. I think Doug's most serious health and safety problem is his untidy wiring. Good luck if you do eventually decide to go ahead.

I haven't gone into too much detail regarding how to wind such a transformer or how to connect it up on purpose; it wouldn't be fair to Doug and I couldn't live with myself should someone following my instructons ended up either dead or seriously injured. My notes are added just to let everyone know there is a very good method of installing cheap 3 phase available and I'm more than happy to let Doug the expert sell you the DVD's which give comprehensive details of how to do the work safely. The DVD's with a running time of around six hours are far more interesting to me to watch than the usual rubbish programs now put out by all channels on TV.

Thanks everyone for your replies; I'm pleased the thread has generated some interest.

Kind regards, Col.
:D Cheers Col. Being a school teacher, with all the 'Elfin Safety' regulations and the prevalent social attitude of 'blame the teacher - doesn't matter what happened, blame the teacher', I suppose I'm more paranoid than most and tend to 'risk assess' as I breathe.... ](*,)...that doesn't mean I won't do it...just that I look before I leap. I'm sure someone who has been in the mining conditions you've experienced, with the ever-present dangers of fire-damp (methane, you modern kids) and cave-ins, you need no advice(?) from me. It's just that I have plugged my body into 240v/50Hz in the distant past and was incredibly lucky to be thrown off the live terminal; I had bad memories revived when I saw your installation. I fully take all the points you make, but I also remember working in industry many years ago with the constant mantra: "Accidents don't just happen, they're made to happen". Stick that perspex up Col! :D

As to when I'll get 'a round tuit', I'm not sure; I have an AGS in bits for what seems now to be its second millenium and a spouse who wants a chimney breast removed. Now. Before we go on holiday in two weeks. :( Certainly, I want summat in there and soon - as Bob 9fingers knows, I picked up a stonking great 3ph/2kW motor that I hoped to put in the AGS, so I need to get off this keyboard and make progress!

There is little original in the DVDs/Book from Doug.
Anyone would think that he invented the auto transformer from the way he goes on. All he has done is use a higher voltage on the artificial phase of a static converter which will give it an element of constant current compare to a normal static converter.
I've only managed to sit through one DVD so far which is very muddled and despite starting in a classroom style of drawing on a whiteboard soon deteriorates into haphazard unstructured experimentation. He also makes the unforgivable mistake of comparing power efficiency by multiplying voltage and current and ignoring phase angle.
It is quite hard work to get to the bottom of what he is driving at mainly due to the expectation of it being something revolutionary when in fact after wading through the dross, I'm left with a feeling of 'Oh is that all its about'.


Many thanks Bob for your frank reply and I'm sorry to hear you are not impressed by what you see whilst viewing Doug's DVD's. Not everyone is well versed in electrical work and I'm certainly one of these so perhaps we see what Doug is about differently and I respect your views.

I found the DVD's highly instructional and informative; so much so in fact that I now have a very cheap 3 phase system installed in my garage that performs better than an expensive manufactured static converter. I admit my electrical ignorance and do so in front of the world. I think Doug deserves more credit than you are perhaps allowing him after all if his method is not unique then why did my static converter perform so poorly compared to Doug's transformer method.

Why don't static converter manufacturers adopt Doug's method thereby producing a means of providing full power from the press of a button. I certainly don't have all the answers but I have the result of Doug's method and I'm happy with it.

Doug is not a professional at producing DVD's so please cut him a little slack; spending the money to buy the three DVD's was money well spent for me; I've already mentioned Doug's untidy wiring and that I used a shuttle to wind my transformer but in the end Doug took me as a novice and taught me to make and install his transformer method with little difficulty; yes he does tend to go on but I could and did ignore this as I don't know any better; I was more interested in installing cheap 3 phase than watching a perfectly produced DVD with all the bells and whistles.

I didn't find it easy having to keep watching the DVD time and again during work in progress and taking notes; obtaining the donor transformer was incredibly hard work in the icy conditions; winding the wire and pulling it tight whilst arranging it neatly opened up a small cut on my finger; I was working in a Yorkshire black hole; I had to go out and buy the wire; I had to move this heavy transformer around entirely on my own and after winding and completing it install it to the ceiling in the garage but I didn't once think about the DVD quality; I simply got on with the job as I wasn't used to this kind of project and at times it was a bit scary especially when I threw the mains switch for the first time and tripped the 30A breaker. I don't give up easily Bob and I had seen Doug demonstrate the starting capability of his transformer method and I wanted the same performance in my garage. For me it was well worth the effort and I learned a great deal at the same time. The only downside is that playing around with so much voltage and current could prove lethal through making a single silly mistake; I try my best to work safely but on this project I double and triple checked everything before touching anything and made absolutely sure the power was turned off and the capacitors were discharged; a professional used to working with electricity would have done the work in much less time but at least I took as much time as I needed and got there safely in the end.

I am unable to give a technical appraisal comparing Doug's method to other methods in use as I simply do not have the knowledge but without Doug's DVD's I wouldn't now have a 3 phase system installed and working in my garage giving full power so I take my hat off to Doug for producing the DVD's.

Many thanks for your kind words Tomyjoiner I'm just doing my best to provide a bit of information as "Unique3phase" is little known this side of the pond.

Kind regards, Col.
Well an hour'ish ago I was going up to bed, but decided to read this post. Now I'm going to wake up with red eyes. I would like to thank the OP/retired/Col and Bob and others for red eye. Sensible now I did find it all very interesting and certainly worth a thought.

Many Thanks

Sent using my acer 9300 laptop with two finger tapper.

Many thanks Sam; I've a bit more time at the moment so I can catch up a bit.

I can well understand your thoughts whilst reading this thread with you having come into contact with live 240V; I'm pleased you are still here though even if it was a hard lesson learnt and of course you will be very wary now of all things electric; I don't blame you.

I'm like you though Sam inasmuch that I think things through before jumping in especially where my own and others safety is involved. I was into risk assessment in a big way at work with three departments to look after. The hours I spent covering every job doing the job and writing up risk assessments. I would actually work each job and write up working instructions; one copy was posted in a prominent positon on the job another copy was held in file; each copy had to be checked and countersigned. This was about the biggest waste of time I've ever seen invented. All it did was create a lot of extra work for me and in the end who actually took the trouble to read the notices?

During my time in the pit; health and safety was given priority but applied with common sense and we were encouraged to think about safety. These days it appears common sense has gone out of the window because a machine that is not fully guarded must be safe to use? Aged 15 I was exposed to massive machinery with huge cast iron gears spinning away only inches from me; line shafts with fast and loose pulleys and lots of big flat drive belts wizzing around; underground whilst the deputies were shot firing; I never felt unsafe as I had been instructed by top professionals what was safe to do and was not safe to do. We didn't need masses of guarding on machinery neither did we need to wear a suit of armour just to knock a nail in; I only ever saw one serious accident and that was caused by a roof fall that crushed a big conveyor and injuring one person who survived to tell the tale. Health and safety is very important but when it comes to me watching an advert on TV where a guy has sued his company for giving him the wrong ladder to use the mind boggles. Bring back proper training applied with lots of common sense.

Good luck with your motor Sam and keep safe. I have one of these motors on my bench that I'm checking over for a friend. Yes they are big and heavy but during my 24 years at Brook Motors I've handled hundreds of huge motors from the Guiseley factory that must have weighed 3 tons or more.

This reminds me of a day when I was moving one of these big motors from Export into Home Trade Despatch; as I came up the yard with the big forktruck a team of pile drivers were busy sinking piles for a building extension; as I drew near they stopped work and stared at the motor; one guy asked what such a motor would be used for; I replied it was going up town to a DIY store and it was to be fitted with a 3/4” Jacobs chuck; a guy had bought this one for use in his workshop at home. As I drove off I realized these guys had hung onto every word and I felt rather guilty at the joke. On the return journey I stopped and explained not only what such motors would be used for but gave them a bit of background as to what the company manufactured explaining motors of all sizes could be bought from the smallest you could lift with one hand to the one they had just seen to cover any application.

Oh dear Malcolm; I'm sorry to hear we are keeping you awake at night but I'm delighted to hear you think it worth it and find the thread of interest.

I started the thread and I find it interesting especially Bob's response which I value and I would like to eventually hear that Bob actually does have a go at Doug's transformer method just to be able to compare performance against a static converter. I certainly don't have all the answers and am always happy to hear other peoples views and opinions; it's what these forums are about after all. It's time I got something done before another day is over.

Kind regards, Col.

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