wood lathe motor

Discussion in 'The Projects Forum' started by jchal3, May 31, 2013.

  1. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    Hello all, I inherited a wood lathe built in the 1930s. The motor is 220v 3phase, but the wires have all been disconnected and are not labeled. I know that the wires went through a switching mechanism that would run the motor in four different speeds. The motor has 9 wires. What I woukd like to do is find which wires are the high speed coils, then run those leads off an inverter so I can operate the machine on 220v single phase. I will attach a picture of the motor plate, the motor, and the switching mechanism. I am not really worried about the switching mechanism because I can control the speed with the inverter but maybe it will help answer the following question..... how to I find the high speed coil?

    Any help would be appreciated.

    It is almost like the motor is designed to run 480-220, and you just put 220 to the 480 coils to run in a slow speed.

    Will have to upload pictures when im not on my phone
     
  2. Dodgydave

    Distinguished Member

    Jun 22, 2012
    4,979
    744
    Ideally pictures say a thousand words,any name plate on the motor?
     
  3. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    finally got a chance to get to a computer.

    Here are the pictures mentioned in the first post. The motors, the speed controlling switch, and the motor plate.
     
  4. Dodgydave

    Distinguished Member

    Jun 22, 2012
    4,979
    744
    Looks like a 3 Phase motor, it may be wired like this

    first job is to meter the wires out in Ohms to see which are joined or not.
     
    Last edited: Jun 1, 2013
  5. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    The switch allows for four speeds.... is that possible to do by varying the connections of a two speed motor
     
  6. Dodgydave

    Distinguished Member

    Jun 22, 2012
    4,979
    744
    Ok it may be wired star(wye) and delta modes to give different speeds, any ideas on the switch wiring?
     
    Last edited: Jun 1, 2013
  7. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    I know it is wired in star. I found a wiring diagram but it is so faded it wouldnt show up on the camera. I could make out that it was drawn in 1930, and there were 4 star connections with l1 being tied together in all four stars. Ill try to get a better photo of it to post, or ill try to sketch it myself
     
  8. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    okay, no laughing, here is the sketch as best I could tell from the wiring diagram.
     
  9. Dodgydave

    Distinguished Member

    Jun 22, 2012
    4,979
    744
    Right so you need to meter out the common wire and then you can find the others , looks like they are all in star format.
     
  10. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    Forgive my stupid question, but there will be four pairs and a ground. Correct?
     
  11. Ramussons

    Active Member

    May 3, 2013
    557
    92
  12. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    I must have not been thinking last night. It should be three pairs and thecremaining three shoulx be the internal star....correct?
     
  13. williamj

    Active Member

    Sep 3, 2009
    180
    32
    It has been decades since I've seen drum controllers like those. I worked on overhead cranes and we had motors and controllers like those on some of our older cranes.

    Dodgydave's coil drawing is spot on. Speed control was done through a series of resistor banks to drop the voltage for the slower speeds. There would be three sections, with three contacts per section, in the drum controller, one section per phase. Each section would feed voltage through a different resistance value, one value per contact, for each speed for a total of three speeds.

    But like I said, it was a LONG time ago.
     
  14. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    William, the actual schematic says it was drawn 6-6-30. So yeah, a while ago. So the switching mechanism I have actually changes the resistance? I kept thinking they were straight switches that changed the coils. So do you think hookingvthe motorvto a vfd and bypasding the switches would work?
     
  15. Dodgydave

    Distinguished Member

    Jun 22, 2012
    4,979
    744
    Well if that's the drawing, looks like its got a DOL starter switch built in that works across two phases,

    L1 goes to the Common rail, and L2 & L3 are put onto each pair of windings to set the speed,

    Have you worked out the common wire yet?
     
  16. jchal3

    Thread Starter Member

    Dec 13, 2009
    78
    0
    No I havent yet. Right now none of the switches are hooked up. I plan to meter out l1 l2 and l3. Then im just going to use an inverter to control the speed and bypass thd switch. Does that sound like it will work?
     
Loading...