3 phase electrical help,

Discussion in 'DIY' started by pegasusbranding, Nov 3, 2010.

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  1. I have just been given one of these machines, SINGER 457 INDUSTRIAL 3 STEP ZIG ZAG SEWING MACHINE£695 on eBay (end time 04-Nov-10 17:05:43 GMT) I dont have a clue about electrics though, and I shant be doing anything without a expert. At this stage I just need an idea on what to do. The machine is 3 phase yet my small workshop in the garden has just 240 volt domestic power. Would I be better getting 3PHASE installed or swapping the motor for a 240volt one, or is they a converter which will plug into my normal 240v plug socket and I then plug the machine into the converter.

    thanks for any replies
  2. Peg, I assume it is 110? if so just buy yourself a transformer off of ebay>
    I have no electrical knowledge and am sure the sparkies on here will better inform you what to do.
  3. You would need to rewire the motor as per either of these diagrams


    It is feasible but the problem you would have is that the motor would not run as smoothly as it will as a 3phase unit, along with the direction of rotation.
    The cost of having your garage supplied with three phase would be expensive to exhorbitant dependant on the length of cable run from the supply.
  4. TheIronDuke

    TheIronDuke LE Book Reviewer

    Anything to do with electrics, get a qualified electrician. Unless it is on a tank. In which case, get a hammer.

    Seriously for a moment, do not **** with electrics unless you know what you are doing.
  5. Your domestic supply is single phase. To get 3 phase, your electricity utility would have to run a cable from the local substation to your house - a bit extreme just to run a sewing machine, even if they were willing to do so! You'd be better off getting a 240 v single phase machine, or if your heart is set on that model, you might be able to replace the 3 phase motor with a single phase jobby, as long as they are of the same frame type.
  6. **** all of the advice above. This is from a proper Elec. Eng. me.

    Buy a single to 3 phase invertor. You get them new on Ebay for about £80 for a 1 horse power invertor (that's 740 watts). Very easy to wire, but get a sparky to do the job. It shouldn't be more than an hours labour.
  7. As the Duke states, if you do not know what you are doing with electrics stand back and let someone who is qualified carry out the work.
    Electrics are a dark art in themselves. It can be done, but you need someone qualified to install the unit.
    If you don't understand the diagrams I posted then don't play with it, if the person doing the work doesn't understand the diagrams they are not qualified and shouldn't be there.

  8. Or move here (Germany), we have 3phase in the Kitchen for the cooker!
  9. Thanks for all replies, I havent seeked any advice from anyone yet this post was my first port of call as I just found out and got hold of the machine today, I may leave it as it is for the moment as I plan to move into a industrial unit sometime next year if all goes well, I shant be installing any electrics I will always get a possessional, I also need to get the machine serviced to make sure it will be fit for use.
  10. if you only have one machine to convert, I would suggest a SPN 230 motor or better still a variable drive. You can buy a converter if you have multiple 3 phase machines (hundreds) or consider a supply upgrade from tyou REC (thousands)
  11. TheIronDuke

    TheIronDuke LE Book Reviewer

    Jesus. To quote Michael Caine in Zulu... "I suppose there is the place for the gifted amateur". But in 1879 they didnt have 3 phase so what do they know? Go for it. Stick your finger on the end of the wire and see if it buzzes.

    Do. Not. ****. With. Electrics. Unless. You. Are. Trained.

    My swimming pool is heated and the extractor works from a street lamp half a mile away. When it fucks up, I call the qualified electrician who sorted the job. I dont try and fart about with it myself.
  12. This bloke is right. I have seen them in action and they are pretty good
  13. 12v is, as already pointed out, correct. Rewiring the motor as suggested by Lance_corp_more_rant, whilst feasible in theory, is not a workable solution for several reasons. An inverter will do the job quite well, but they have a habit of tripping following repeated start or prolonged running at load, so take advice about which one to buy should you go down this route. My own advice would be to sell the thing on e-bay for several hundred quid.
  14. TheIronDuke

    TheIronDuke LE Book Reviewer

    Ah, I give up. Can anyone rewind a Wico trip Mag off of a 1932 McCormick-Deering (International Harvester clone). The 3HP version. Cash waiting. Can swap for a jet-ski.
  15. Either:

    1) Get a 1ph to 3ph inverter.
    2) Change the motor for a 1ph one.
    3) Give it to me as I have 3 ph and need an industrial sewing machine for a couple of months. You can use it whenever you want. :)

    The general advice about not messing with electrics unless you know what you are doing stands. :)