How to use three phase motor in single phase power supply

This time,I would like to share some important knowledge that I used it when faced emergency or critical situation.What are you doing if have only three phase motor and single phase power supply available?

How to use three phase motor in single phase power supply?Actually three phase motor can operate in single phase power supply  with the help of a permanent CAPACITOR.This small thing (capacitor) very helpful to make three phase motor running in single phase power supply.

As per our last discussion about three phase motor,normally it’s have two(2) common winding connection ,STAR or DELTA connection.In this post,I explained how to wiring the capacitor in three phase motor,how to change motor rotation,how to estimate value of capacitance and selection of suitable capacitor.

How to install and wiring capacitor for three phase motor with single phase power supply?

1) Wiring of capacitor for FORWARD rotation

-For FORWARD rotation,we must install capacitor  in DELTA connection as per drawing below.

* symbol –> The change of the connection terminal * of the capacitor allows to invert the turning sense of the motor.

forward rotation capacitor


2) Wiring of capacitor for REVERSED rotation

– For REVERSED rotation,we must install capacitor in any two phase of winding in STAR (Y) connection as per drawing below.

* symbol –> The change of the connection terminal * of the capacitor allows to invert the turning sense of the motor.

reverse rotation capacitor

Output of Motor

We must to consider the output of motor when we converted from three phase to single phase power supply to match and suitable with our application.But we cannot get the actual value due to so many aspects we must calculate and it’s so complicated.So we can estimate the approximate value of motor output as per percentage (%) below :-

How to choose suitable capacitor?

This is very important decision making that we must consider about size of capacitor when plan to running the three phase motor in single phase power supply.If not choose properly,it might be effected to motor condition and performance also can damaged the winding of motor.

Below is approximate value of the capacitor that required.We must consider the Working voltage VS Network voltage to avoid any damage on the three phase motor winding or capacitor it’s self.Please refer table below :-

table of capacitor value


  1. what is a vsd and it works to the motors.explain the importants of it to both the motor and the consumer

  2. Please i want to get a schematic wiring diagram which is illustrating how wires are been connected to contactors, and auxilary contactors and timer and push start and stop botton in a 3phase star/delta diagram.
    Thanks from stanley

    • i want that same wiring sceme with each and every terminal of contactor ,relay ,timer st/stp push button ,ON/OFF/TRIP LAMPS

    • mikon power electrics kenya says:

      You can contact mi by sending yo email so that i can send you the diagram

      • Dear sir,

        We want to run 3 phase submersible pump set through single phase .please guid me sir
        In our phase to phase Voltage R phase to y phase 230V AC , R Phase to B Phase 230V AC and YPhase to B phase 120Volts .So PLeas guid me sir

        • Hi marimithu,
          I am in the similar situation. Did you find a solution Om how to go with this,
          Even we have a 3 phase 230 V submersible motor and supply of single phase 240v.
          Any help is much appreciated.

          • Hi Nasir,
            You can try to use VFD or inverter to drive your submersible pump.The inverter input power supply is single phase 240V and it will convert to 3 phase output to your motor.But please consider your Inverter current (ampere) rating same rated or higher than motor FLA.Rule of thumb to sizing your inverter is –> FLA x 2 = VFD current rating.
            NOTE : Fusing or Circuit Breakers should be sized to match the INVERTER input current rating, NOT the motor current rating!

  3. how can i get variable sources like dc , ac ,varible frequny ac from 440v

  4. Can any one help me I got a car lift and it got a three phase motor on and I got only single phase at home .Here is the spec on it. V 230\400. A. 21\12.7. KW. 4. What size cap can

  5. i wil disgne a one motor and work 3

  6. Gabe Edward says:

    I have a motor with the following ratings star, 1350w,380v,2850rpm,50hz,2.4A. and delta 1000w,220v,4.2A.pls how and what value of capacitor can I use to covert this water pump to a single phase?

  7. We are using 1 phase submersible pump now running manually, please send drawing for automatic operation for using timer.

  8. Narendra Anjana says:

    How to start three phase motor 12 hp in single phase supply please send me a digram or send me video to my whatsaap… my cell number 09950757602
    Thank You

  9. Reuben says:

    The control switch for 3phase pump was damaged,can it b possible to run in single direct from distribution box using 20Amp?

  10. Annasaheb Nevade says:

    I have three phase 2.1kw motor want to run in 1 phase missing? what to do voltage is 380 volt. it is possible as using 440v capacitor as per ur above table? reply me my mail ID whatsapp no. +919423984609

  11. Sachin DB says:

    How to start three phase motor 3hp in single phase supply please send me a digram or send me video to my whatsaap… my cell number +919901131138

  12. ravinder yadav says:

    How to stat single phase submersible motor with vfd without capacitor

  13. Very help full article.

  14. Dhirendra kumar says:

    sir, Haw can inverter connection in house please send me a digram in my email

  15. can a one phase motor physically attached to a 3 phase motor (with only phase attached) run up the 3 phase motor to speed and then turn on the switch to the 3 phase motor and keep it running? any power loss to the 3 phase motor? current increase?

  16. P.SELVAN says:

    I need PDF format on Three phase fan to be connected with single phase by adding the capacitor.

    • Hey,

      If you’re still looking for the answer to your question I recommend asking your question on Quora where there is a great community of active, helpful and highly knowledgeable people who are sure to help you with what you need to know and understand!

  17. gabe Edward says:

    Gabe Edward
    I have a 3phase water pump with the following characteristics,for star v=380v, i=2.4A and for delta v=220v, i=4.1A.the power of the pump is p=1.35kw, the speed n=2850r/min at 50Hz. Pls tel me the type or types of capacitors to use and its values to run this pump on a single phase power supply. Pls send to thanks.

  18. Ramon Barotillo says:

    What types of capacitor can be used to run three phase motor 1.5Kw at 220 volts single phase.

  19. is it possible to design single phase and three phase motor using same stator (using single motor) slot by putting both single phase and three phase winding in same stator slots.

  20. can we use 3 phase motor with out using starter

  21. please, I have a brand new three phase motor to be installed on a single phase phase network. how do I go about it? also, I don’t know if the motor is already connected in stat or delta or am I the one to do it? I will highly appreciate your opinions. thanks for reading through.

  22. William says:

    Hi sir,can we use this configuration for a larger motor?? Let’s say 30 hp motor??

  23. Hey sir i have 10hp three phase motor, please can you send for me the wiring diagram of connecting this motor on a single phase supply using capacitor and which size of the capacitor should I use, sent to me on whatsapp 0728525990

  24. Tulshiram Sarode says:

    hi sir i have 3hp three phase motor please can you send for me the wiring diagram of connecting this motor on a single phase supply using capacitor and which size of the capacitor should i use,sent to me on whatsapp 7083071434

  25. Can you supply the start and run capacitor specs for a static phase converter to operate a 460v 15kw 3 phase motor?
    Thank you,

  26. please i need a simple wiring diagram of how to connect a automatic star delta with the control unit using 220v timer and a 24v relay

  27. Sangamesh says:

    Sir, I have 1phase texmo submersible pump. From the starter the connection should be RYB. But motor works only if it is connected in YRB. What is the prob. This is happening only at my home.. not at other power source..

  28. Hi I tried this but I got a challenge. The capacitor is continuously burning. What could be the problem? Please help me.

  29. Hi….eny electrical problam call me 9159478044 RAKESH from mannargudi thiruvarur

  30. Neeraj says:

    Hi marimithu,
    please tell me in 7.5 hp 3 phase moter we use your upper dia. but not shore value of cap. is 400mfd. or any please clear that . thanking you

  31. Mansoor says:

    i have final year project i have construct
    rectifier 220 to 330 V accurately
    Hex bridge (1200 v and 35 A rating) with two capacitor Bus 440 V rtin and 1000uF
    control circuit contains ir2110 gate driver tlp250 opto couplers and arduino is here to generate spwm pulses
    but i am scared how to test this and how measure voltage
    would it directly run the 1hp motor or any other methodology
    kindly gude me

Speak Your Mind