Tuesday, April 3, 2018

Single Phase Motor Winding Resistance -Start Run Common

This post is about the single phase motor winding resistance. In this post you will learn about the single phase induction motor winding resistance. In the single phase induction motor we have two types of winding. In which one is called main winding also known with running winding. And 2nd winding is called auxiliary winding also known with starting winding.

single phase motor winding resistance

Single Phase Motor Winding Resistance

This is very important to know about the single phase induction motor winding resistance. Because we did not know about this, we can connect the supply and capacitor to the motor. Or we cannot do the capacitor connection with single phase motor. As I written above that single phase motor have two types winding and each winding a have there resistance. But which winding resistance is high then other winding, that's is important point...

In the single phase motor, the main winding is make from thick wire which means that this winding will me low resistance then starting winding. The starting winding is made from the thin wire (SWG) which means that this wire will be high resistance then other one. 

For example if the main or running winding is made from the 21 SWG and its resistance is 2O ohms. And the starting winding is made from the 24 SWG wire. The resistance of this winding will be high. 

We know that the point in which the two winding connect together is called common point. And the main winding resistance is low then auxiliary winding. which means that the low resistance between common will be the run and high resistance with common will be start. So the supply will be goes to the common and run and capacitor will be connect between the run and start. 

This is single explanation of single phase motor winding resistance, However if you want to learn more about how to identify the start run and common in a single phase motor then read the following articles for complete understanding... 


I hope know you will got some knowledge about single phase motor winding resistance and now you will be able to find about the main and auxiliary winding in single phase induction motor. However if you have any question about this post then you ask your question in the bellow comment section.


  1. This comment has been removed by the author.

  2. Assalam o Alaikum Sikandar Bahi.
    kia hal hain.
    Mein Electrical Technician ki job ka lia tiyari kar raha hon aap ki website say bahut faidah mil raha hai.
    Jazaka Allah
    Munawar Abbas
    Dera Ghazi Khan

  3. Run + Start = Total Resistance
    Run = Total Resistance - Start
    Start = Total Resistance - Run

    On a simple motor with three leads there are a total of three combinations to measure. You measure the resistance of each of the three combinations. The highest measurements is the total resistance of both windings together in series. The next highest is the start winding. The lowest measurement of resistance is the run winding.

    The motor in the picture with the extra two wire for the start capacitor is a little more tricky, but if you disconnect the capacitor and measure the resistance of those two wires, it should be both the start and run together and is the total resistance of them both.

  4. I must express my gratitude for your kindness supporting men who must have help on your concern. Your special commitment to passing the solution across ended up being wonderfully advantageous and have continually helped many people much like me to get to their aims. Your personal helpful help implies a great deal a person like me and much more to my office workers. Best wishes; from all of us. https://royalcbd.com/cbd-legal-status/