Help needed with lathe electrical’s!!

  1. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    I’d better start looking for the BIG lever bar!
     
  2. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    Brightspark,

    do I just have to have the lathe plugged in to the running phase converter, or do I have to have the lathe ‘running’ or at least trying to run?
     
  3. eLuSiVeMiTe

    eLuSiVeMiTe Member

    Messages:
    13,001
    Location:
    Bedfordshire England
    Iirc it's a 2 speed motor on these.

    3 speed according to lathes uk
     
    Memmeddu likes this.
  4. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    It’s the mk2 vsl. It’s got a constantly variable drive via a sheathe system.
     
    eLuSiVeMiTe likes this.
  5. carbon

    carbon Member

    Messages:
    1,690
    Location:
    S. Glos. U.K
    The second diagram shows control voltage at 415v as it doesn’t have a neutral connection but 110v possibly is still only for the light. The diagram doesn’t show voltage for the light only says low voltage. Check what voltage the coils on the contractors should be operating at
     
    Memmeddu likes this.
  6. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    This is the electrical box on mine.
    upload_2020-9-20_18-44-58.jpeg


    Having got in and had a look at the contactors and pretty much everything thing in there says 110-120 volts.

    upload_2020-9-20_18-46-23.jpeg

    Any more thoughts?
     
    Memmeddu likes this.
  7. carbon

    carbon Member

    Messages:
    1,690
    Location:
    S. Glos. U.K
    I can’t make out the wiring to the fuses but looks like only one of the three fuses is fitted rather than all three
     
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  8. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    I had noticed that too. They should be 20a like the one that’s there. The bottom of the fuse holder says 500v so obviously high voltage.

    I know they’re not they’re but it was operational when it was disconnected and removed. The seller says they unplugged the 110 from the transformer and cut off the wire that went to the phase converter.

    so what’s changed? It ran without those fuses.
     
  9. brightspark

    brightspark Member

    Messages:
    31,752
    Location:
    yarm stockton on tees
    so where are the 3 phases connected to now then from the converter
     
  10. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    Brightspark,

    forgive me but I don’t understand :dontknow::ashamed:
     
  11. julianf

    julianf Member

    Messages:
    5,064
    Location:
    devon, uk
    I changed the motor on my s&b model m.

    I don't think it was that expensive, but it was years ago.

    I doubt your lathe *needs* 3ph, so a motor swap might be the simple option?
     
    Memmeddu likes this.
  12. carbon

    carbon Member

    Messages:
    1,690
    Location:
    S. Glos. U.K
    Think i would check continuity through the contractors from the incoming supply with the power disconnected on all three phases to make sure all three phases make it out to the motor
     
    Memmeddu likes this.
  13. brightspark

    brightspark Member

    Messages:
    31,752
    Location:
    yarm stockton on tees
    the feed to machine was fed through the 3 fuses originally. where are they connected now as 2 are missing
     
    eLuSiVeMiTe likes this.
  14. carbon

    carbon Member

    Messages:
    1,690
    Location:
    S. Glos. U.K
    From the diagram incoming phases should go through one contactor then onto the fuses then onto the other contactors. If fuses are missing it could be trying to run on one phase
     
  15. My Old Landy

    My Old Landy Melting Metal

    Messages:
    242
    Location:
    Buckinghamshire UK
    The wires to the blank two fuses are cut off. It looks wrong to me!
     
  16. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    The wires coming out of the bottom of the 2 fuse holder are indeed cut off. They look like they’ve been like that for some time. I had thought that they were to do with the original 110 transformer that’s no longer in there.

    I think it’s time to break out the multi meter again.
     
    Memmeddu likes this.
  17. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    So I’ve ascertained that the holder with the fuse goes to a safety cut out to turn the lathe of if the end door is opened whilst its running.
     
  18. brightspark

    brightspark Member

    Messages:
    31,752
    Location:
    yarm stockton on tees
    where have you connected the 3 phase supply wires to in the control box
     
  19. carbon

    carbon Member

    Messages:
    1,690
    Location:
    S. Glos. U.K
    Think you need to make a new wiring diagram based on what you have in the machine as it doesn’t look like it corresponds with either of the diagrams that you have posted previously, or at least check the three phases are getting out to the motor
     
    Hopefuldave and Memmeddu like this.
  20. farmer_joe Member

    Messages:
    47
    Location:
    Tonbridge, Great Britain
    How do I check whether the phases are getting to the motor?

    move dragged the lathe out and have accessed the motor, I have the cover off the electrical box there.
     
    Memmeddu likes this.
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