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Single phase motor

Discussion in 'Sensors and Actuators' started by gregrae, Mar 27, 2017.

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  1. Bluejets

    Bluejets

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    Oct 5, 2014
    I'd say your connections should be as in the attached drawing.
    1.25 = run
    2.5 = start
    4.4 or whatever is series combination of start and run. ............See diagram below

    Note that direction reversal is by reversing current flow through run winding with respect to the start.
     

    Attached Files:

  2. gregrae

    gregrae

    67
    1
    Jan 12, 2011
    Can you tell me if this post is correct .The one with all the values on it.
    I ran the motor with a drill u1 / u2 ohm reading went down to about 1 ohm , was fluctuating
    Run did not change v1 / v2 but z2w2 / z1w1 did go lower and also fluctuating.
    Can you advise me
    Thank you
     

    Attached Files:

  3. Minder

    Minder

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    Apr 24, 2015
    If there is a centrifugal switch in the motor for the start winding, one should show open circuit at sufficient rpm.
    M.
     
  4. gregrae

    gregrae

    67
    1
    Jan 12, 2011
    There is no cintrifical switch
     
  5. Minder

    Minder

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    Then there should be an external current detect relay to switch out the start winding and 250uf cap..
    M.
     
  6. Bluejets

    Bluejets

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    Mostly but not always.
     
  7. Tha fios agaibh

    Tha fios agaibh

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    Aug 11, 2014
    Huh, you externally hooked up a drill motor?
    Did you hear a click noise while it was rotating? That would be a centrifugal switch)
    Ohm readings while rotating are meaningless.
    The reason I told you to disconnect the wires from the terminal block was to insure an unadulterated ohm reading. Do NOT have the cap hooked up when measuring.
    Minder is absolutely right that the start winding needs to be switched out once the motor starts.
    Don't forget to have the run cap hooked up also.
    Go back to post 4 to see diagram.
     
  8. Bluejets

    Bluejets

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    Oct 5, 2014
    Can you provide a link to the diagram in #4...looks like it has been modified?

    Edit:- ....I think this Op needs to get on to the supplier....I just checked what seems to be the same motor on Ebay and there are conflicting diagrams from the main window describing the motor and that which shows details ( as supplied here) further down the page.o_O

    http://www.ebay.com.au/itm/Electric...730126?hash=item4d424b900e:g:53EAAOSwy4hUTgqx
     
    Last edited: Apr 10, 2017
  9. Minder

    Minder

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    It is usually one or the other, either external or centrifugal, which the OP claimed it had in the TS.
    But changed his mind in post #24.
    It is not a PSC motor so the 250uf is normally switched out at start.
    M.
     
  10. gregrae

    gregrae

    67
    1
    Jan 12, 2011
    Having opened up the motor yes there is a centrifugal switch inside.
    The switch contact is connected to v2 and when rotated it is connected to v1.
    Hope you can make something out of this .
    Thank you.
    # 24 is incorrect
     
  11. Bluejets

    Bluejets

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    Oct 5, 2014
    Fair enough BUT where are you measuring from to get this reading?
    Rotation usually requires around 1/2 to 3/4 speed to changeover the switch so how did you manage that on a 2850rpm motor? Or did you manually change it with a screwdriver or whatever?
     
  12. Minder

    Minder

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    The OP mentioned he opened the motor up, I assume this was an alternative to rotating it?
    If the switch opens up V2 then this is where the 250uf would be switched.
    gregrae is there any connection to the Z2-W2 and U1 from the other terminals?
    M.
     
  13. Tha fios agaibh

    Tha fios agaibh

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    Aug 11, 2014
    I just cropped it but if you Google it you will see it's a standard diagram.
    As I mentioned earlier, dealing with most Chinese suppliers is a nightmare.

    Sounds like we are almost there in figuring out the physical connections, although the start winding ohms sounds a bit on the low side
     
  14. Minder

    Minder

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    From your post on #19 it looks like the 250uf goes from Z2/W2 to V2.
    the smaller cap 40uf goes from U1 to V2.
    M.
     
    Last edited: Apr 10, 2017
  15. Tha fios agaibh

    Tha fios agaibh

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    Probably, but it's hard for me to follow without seeing it sketched up exactly as it is.
    @gregrae, can you do a sketch again including the centrifugal switch connections?
    Shame on motor manufacture for not documenting this on nameplate.
     
  16. Minder

    Minder

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    V2 is a power junction terminal
    And V1 & V2 have power across them for both directions, so the explanation in #30 doesn't quite make sense.
    M.
     
  17. gregrae

    gregrae

    67
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    Jan 12, 2011
    This is the latest drawing .
    I hope this will do.
    Greg thank you
    Hope that we can get some results from this drawing.
     

    Attached Files:

  18. Minder

    Minder

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    From my perspective that does not quite make sense, you have a C.F. Sw in series with not only appears to be the run winding and no cap in series?
    When the switch opens you are left with two winding's which appear to have capacitors connected??
    M.
     
  19. Tha fios agaibh

    Tha fios agaibh

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    Aug 11, 2014
    I agree, something is wrong here.
    Are there 3 or 4 wires from motor itself?
    The CF switch is drawn in series with what is likely the run winding, whereas it should be in series with the start winding which will be the largest ohm value.
    I would disregard the terminals at this point and establish which winding is which. Another words, isolate just the wires from the motor. Then label them with a piece of tape and mark them 1,2,3. Then again tell us ohm readings for 1-2, 1-3 and 2-3. Make sure meter reads zero with leads crossed.

    Then we will tell you how to terminate the wires, caps and Cf switch.
     
  20. gregrae

    gregrae

    67
    1
    Jan 12, 2011
    I have removed the terminal block and only wirers.
    Attached is a drawing and photo.
    Thank you
    Greg
     

    Attached Files:

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