# 3 phase induction motor

#### zobi92

Joined Feb 1, 2014
19
Hello friends

I am using three phase induction motor 380Vac/220Vac Y/Delta.

Now should I required two supply of three phase 380Vac and three phase 220Vac to run this motor on Y and Delta configuration?

Or both Y or Delta can be run with single three pgase supply?

And if i required two separate three phase supply how can I achieve this cheaply?

Joined Jul 18, 2013
22,623
So you want to run the same motor on both voltages?
You can only run the motor alternatively on both voltages, if one supply is 380 and the other 220.
The alternative method of single supply could be a 380v star supply for one supply and feed a VFD from one phase and the star neutral for the lower voltage supply..
Max.

#### zobi92

Joined Feb 1, 2014
19
Sir actually i have to operate this motor on star network and then delta network how could I acheive this ?

Do i need to purchase a motor which runs on 380vac on star and 380Vac on delta?

So you want to run the same motor on both voltages?
You can only run the motor alternatively on both voltages, if one supply is 380 and the other 220.
The alternative method of single supply could be a 380v star supply for one supply and feed a VFD from one phase and the star neutral for the lower voltage supply..
Max.
Sir what I understand is I supply three phase directly when using as a star network and supply from vfd (220vac 3 phase) when using as a delta network.

Joined Jul 18, 2013
22,623
Yes, except on 220 it would be one phase of the 380 and the star neutral to produce the lower 3ph supply.
Although, the 1ph input VFD's are limited up to around 5HP.
If you are using the same supply, what is the reason for the switch.
Max..

#### zobi92

Joined Feb 1, 2014
19
Yes, except on 220 it would be one phase of the 380 and the star neutral to produce the lower 3ph supply.
Although, the 1ph input VFD's are limited up to around 5HP.
If you are using the same supply, what is the reason for the switch.
Max..
Sir i have to design a star delta starter just to approve my semester project.

Sir can i consider three phase step down transformer as a option?