Terminal connection for induction motor

When we install a new electric motor for our application,we need to determine the voltage of power supply.Why it so important when we dealing with electric motor?

Ok..electric motor manufacture design their product can suit with several value of power supply around the world.It made the motor can used at any countries without worried about their power supply value.

The value of voltage for all country’s around the world have variant such as 200 VAC,220 VAC,415 VAC or 440 VAC  for 3 phase.That why some motor manufacture design their motor can operated with 2 types of voltage.So it available for use to any country around the world.

How to determine motor terminal connection for suitable voltage?

This part is very important to ensure our electric motor installation is done perfectly and running properly.If we wrong setting for voltage value connection for induction motor,it can cause serious damage.

But dont worry,this time i explain detail how to determine a motor terminal connection for suitable with our power supply.The key is motor nameplate.We can found the motor connection and their suitable voltage value.For more detail,please refer a picture below :-


From this motor nameplate,we can see it have 2 connection and 2 voltage value.If our power supply voltage is 415 VAC for 3 phase,we need to setting the motor terminal in STAR connection.

It mean terminal cooper plate W2,U2 and V2 connect in one line.Here i attached picture about motor terminal in STAR position.


If our power supply is 200 VAC 3 phase,we need to connected the cooper bar terminal in DELTA position.It mean, a connection are U1 with W2,V1 with U2 and W1 with U2.It just need to follow the diagram shown in motor nameplate.


If you want connect the induction motor with star delta starter,what you must to do is take out all cooper bar from motor terminal.It mean we not use a cooper bar.Because the star delta starter use a 6 cables for run the motor.

I hope from this post it can help all of u how to connect or perform termination job for induction motor.It is very important to ensure our motor running in good condition and avoid any damage.That why the nameplate of motor is very important…


  1. sir i have one question is that, my induction motor is also 3 phase. requires 415v volt. 12 terminals are comming out form motor winding.and i want to connect it star-delta connection so out of that 12 terminals which should connect to power cable

  2. laxman says:

    sir which purpose we are use in star or delta connection.in a 3 phase induction motor.if we have 11kw 3phase motor in simple purpose motor .then which connection is better star or delta….

  3. RAJASEKAR says:

    In vfd and star-delta stater bypass panel vfd only have 3 outgoing terminal and star-delta starter 6 terminals.how to connect terminal.

    • if you want used VFD to replaced star delta starter,first thing you must do is to determine motor connection either star or delta.Please refer motor nameplate for the connection.
      As your known for star delta starter,no cooper bar install at motor terminal.that why it used 6 wire.For other starter used 3 wire with cooper bar at motor terminal

      Example nameplate motor :

      star connection : 415 VAC
      delta connection : 240 VAC
      Your power supply is 415 VAC
      for more detail please refer my post : dual motor voltage

      * You need to install terminal bar with star connection and connect 3 wire from output VFD to the motor with right phase.i already explain in this post..

  4. Robar says:

    I am looking for an induction motor which has both ends of phase windings accessible, like the motor shown in this article. I want a motor with 1 hp power and 1700-1800 rated rpm. The motor will be used in vector control. Can someone please suggest some good motors (by Baldor, Leeson, Reliance etc.). I want to have the freedom of connecting the motor in star or delta configuration. A 12 terminal motor (with 2 windings per phase, connected in series or parallel for different voltages) will also serve the purpose. Please help.

  5. sohail says:

    i have 3 phase indction motor for aerator with 6 terminal like u1-v1-w1,u2-v2-w2, and 6 wire coming from the panel board. RYB , how will i do connection of the motor plz tell me the right connection.

  6. mohammed says:

    what is the different between delta and star ?
    i want explain about these.

  7. I have gone to research alot about VFD and I stumbled in this website. I have bookmark this website for my future reference.

  8. sir i have small dout ,i have induction motor 220/380 volt but i have only 380 volt 3 phase .how can i connect the power supply to the motor

    • Hi,
      Check your motor nameplate for motor connection.A name plate will state the voltage and type of connection ( star @ delta ).For more detail,please take a photo of your motor nameplate and i will try to check it for you.

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  10. Hamis Nyangwa says:

    great job bro.

  11. Subin Idicula says:

    when motor connection is wrong , then how to check continuituity from either motor or panel side..

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