Delta and star

MaxHeadRoom

Joined Jul 18, 2013
20,675
I assume you mean an AC Induction motor?
The star delta arrangement allows for two different voltages levels to be applied, either for operation on different level supplies, or to start in a Star-Delta fashion where a high load is present and a 'Soft-Start' is required.
Max.
 

Thread Starter

hero22222222222

Joined Dec 22, 2019
71
I assume you mean an AC Induction motor?
The star delta arrangement allows for two different voltages levels to be applied, either for operation on different level supplies, or to start in a Star-Delta fashion where a high load is present and a 'Soft-Start' is required.
Max.
Sorry I do not really understand. I might not have made the question clear.

I was playing with a 3 phase induction motor but when I made a delta connection my machine was about to stall above 0.6 Nm torque but this wasn't the case when I used a star connection. I'm not sure why this happened.
 

MaxHeadRoom

Joined Jul 18, 2013
20,675
What is the motor rated at?
It will have a different voltage rating for Delta and Star.
It sounds as though you are using the same supply?
Max.
 

Thread Starter

hero22222222222

Joined Dec 22, 2019
71
Hello Hero2222222222. Forgive me if I missed it a 2.:p Star also known as wye, three phase also known as polyphase. I have attached this link.a very excellent explanation. Please review and I'm sure you will have more questions that we would be more than willing to answer. I did not mean to be so presumptuous I am new here as well.
https://www.allaboutcircuits.com/textbook/alternating-current/chpt-10/three-phase-power-systemhi i hs/
I read this and it hasn't really answered my question on why the machine nearly stalled above 0.6Nm with delta connection but not with star connection
 

Delta prime

Joined Nov 15, 2019
329
This gentleman beat me to the punch. If I may be so bold to quote.
Your motor is meant to be connected Δ 230 or Y 380. When you connect Δ, you get full applied voltage across each winding. in Y, you get a voltage divider effect across 2 windings at a time. wye-delta starters are a "soft start" or "reduced voltage start" - they start out in wye, giving less voltage across each winding, and then switch to delta.
torque controllers help reduce mechanical and electrical stress on motor circuits and systems by limiting voltage at start-up. This avoids the over-torque and over-current conditions that happen when across-the-line circuits are completed, like when a basic motor control contactor closes
 
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