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  • #16
    Yes indeed, complexity available through small electronics.

    What you call Wye used to be called Star or just Y.

    What is relevant to the OP is that the aim of designing windings is to achieve as little resistance as possible, the limitation being that wires have to be large in diameter and size is limited to the space available.

    So using an Ohm meter (which is really a voltmeter sending some voltage across what is read), very low readings will still be found.

    Ohm meter has limited usefulness , as alluded by Rodbolt, because resistances are low.

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    • #17
      Originally posted by zenoahphobic View Post


      Ohm meter has limited usefulness , as alluded by Rodbolt, because resistances are low.

      Not trying to be argumentative about it, but the ohm value is very useful in checking a electric motor, particularly a questionable non-oem part that might be outside of spec.
      If it shows a bit of resistance than its not shorted, if it shows virtually no resistance than it is shorted.
      Lastly, if it shows a lot of resistance then it would draw more current than its supposed to, which will create heat and even more resistance.

      Those values would be compared to a good oem pump or its specs if published somewhere.
      Last edited by Dashunde; 09-03-2015, 12:56 AM.

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      • #18
        Need a good low reading ohm meter; cheap and common digital meters are wanting in getting absolute readings. Usefulness as you point out, in comparative readings. As you know there is no such thing as a short, as there is no measurement of zero. Every conductor has some resistance.

        I get what you are saying about resistance causes heat, causes more resistance and more heat. That is also means of finding poor connections. Not being picky your logic a bit faulty; resistance does not increase current; by definition it reduces it.

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        • #19
          Originally posted by zenoahphobic View Post
          Not being picky your logic a bit faulty; resistance does not increase current; by definition it reduces it.
          Yep, ohms law supports this fact

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          • #20
            Originally posted by zenoahphobic View Post
            resistance does not increase current; by definition it reduces it.
            Load and wire resistance increases current (amp) draw in a electric motor.

            Electric motors will strive to reach a specific rpm at a specific voltage, loaded or free spinning alike, it will still try to reach that rpm and no more.
            When it can not reach its desired rpm at a certain voltage it will draw more amps/current in an effort to reach that rpm.

            Kv is measured in 1000rpm per 1 volt, so a 2000Kv motor will try to reach 20,000 when its given 10 volts whether its loaded or not.

            The physical properties of the motor determine its Kv; primarily how many stator poles & magnets and how many turns does the wire take around each stator pole, and in the case of a 3-phase brushless Kv will vary a lot depending on how its terminated; Delta or Wye.

            To the point...
            A motor wound with high quality wire, will have a lower amp draw than the exact same motor wound up with low grade high resistance wire under the same load.

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