single to 3phase conversion

[AlanBeckett]

This is England. It would be a poor do without Bread and Beer.

Alan

[Retired]

Hi,

Bron has a great dishwasher; I do the lot and don't mind in the least looking up our mountain whilst at the kitchen sink watching the wildlife.

I doubt we'll ever buy a dishwasher just for the two of us and I regard a dishwasher as yet another item to go wrong.

No beer or any alcohol for Bron and me Big Al; we never touch the stuff so never miss it. Give me a pot of tea any-day or even the occasional coffee.

We've never owned a microwave either and possibly never will.

A few months ago I splashed out on a £5 mobile phone putting £10 credit on it. At the last Rufforth meeting I attended I was going to phone Bron to say I'm on my way home only to find this new mobile absolutely dead? More modern stuff to die. When I arrived home I felt like nipping it in the big engineering vice just show what I thought of it. I bought this phone just for the Rufforth meetings and only used it once a month so what a load of rubbish.

I relented and out of curiosity I browsed the web to see if I could find any information as to why my mobile wouldn't charge? I found a site suggesting throw the battery in the freezer for over an hour; I was amazed because it worked and the battery then charged so all I need to do now when I visit Rufforth is take the freezer along?

Kind regards, Col.

[ex 2 Base]

Ed, regarding your talk on making single to three phase converters did you give out notes to the audience, if so could I have a copy. Prior to inverters being readily available and at a reasonable cost, I made several converters for my local model engineering friends. I used 1-1 isolating transformers and paper dielectric capacitors ex power factor correction units. On a couple I used an old motor to make it into a rotary type of converter which worked well. The transformer were obtained from mobile rally's, which are now almost a thing of the past. I would just like to compare my circuit with yours, not making any more as inverters is the way to go, unless unless some one has a machine with a special 415 volt multi speed motor. I am wary of attempting to reconnect a two speed motor from 415 star to 240 delta, sorting out the connections for reversing in star is bad enough.
I was given yet another faulty micro yesterday with a good transformer. A few years ago I bought a transformer for £32 pounds to fix a micro, now you can buy a new one for about the same price. Ted

[Ed_Dinning]

Hi Ted, I did do some so I'll see if I still have them, if not some of the other guys may have them.
Basically on my system you have a 240 to 415 V autotransformer. This feeds phases A & B of the motor. The 415v overwind is continued to 650v or so and feeds a cap that feeds phase C of the motor.
It is normal to have start and run switching of the cap bank and a "balancer" motor helps if available.
There were commercial versions of this available that used a bank of caps and switched them via contactors and a voltage comparator that looked for voltage balance on all 3 phases,.

Ed