is Delta or Star an option for this motor?

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
I recently replaced a 3 phase 2.2Kw motor on a bandsaw so that I could utilise a VFD for speed control. I thought that the original motor wouldnt switch between star and delta as it only had three connections. Looking closer I see that it has six wires coming out to the junction box. could these be reconfigured to make it useable with a VFD controller. If so how would I identify the correct wires?. any advice would be much appreciated. KeithIMG_4270.JPG
 

Reloadron

Joined Jan 15, 2015
5,999
There is a good possibility the six wires are for configuring High or Low voltage, for example 240 or 480 Volts. Do you have the nameplate data for the motor? The nameplate data should tell you what you want to know.

Ron
 

MaxHeadRoom

Joined Jul 18, 2013
23,385
What is the 3 phase voltage you are using? the motor appears as it is already in Delta, (low voltage), there does not appear to be the normal terminals for setting Star or Delta options, where there is normally 6 terminals supplied.
Max.
 

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
What is the 3 phase voltage you are using? the motor appears as it is already in Delta, (low voltage), there does not appear to be the normal terminals for setting Star or Delta options, where there is normally 6 terminals supplied.
Max.
IMG_4264.JPG
thanks so much for your input. here is the plate details
 

LesJones

Joined Jan 8, 2017
3,300
As the motor looks like it was designed to run on 415 volts (Phase to phase.) in delta configuration if it was connected in star configuration it would require 719 volts phase to phase. Which would be 415 volts phase to neutral if there was a neutral.

Les.
 

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
There is a good possibility the six wires are for configuring High or Low voltage, for example 240 or 480 Volts. Do you have the nameplate data for the motor? The nameplate data should tell you what you want to know.

Ron
IMG_4264.JPG
thanks for your response, heres the plate
 

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
As the motor looks like it was designed to run on 415 volts (Phase to phase.) in delta configuration if it was connected in star configuration it would require 719 volts phase to phase. Which would be 415 volts phase to neutral if there was a neutral.

Les.
oh right! sounds like its a non starter then to work with a FVD on 230v ac. many thanks for your help
 

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
What is the 3 phase voltage you are using? the motor appears as it is already in Delta, (low voltage), there does not appear to be the normal terminals for setting Star or Delta options, where there is normally 6 terminals supplied.
Max.
Thats why I thought that the six wires might equate to the six terminals. the motor i replaced it with has the six terminals and was easy to configure to work with the VFD. I have another machine that needs a VFD so before I commit to another motor I am exploring using this old one.
 

MaxHeadRoom

Joined Jul 18, 2013
23,385
Also a 6 pole motor at that rpm. I guess due to fitted to a band saw?
Usually star/delta connecting motors have the 6 terminals laid out 3 above one another.
Max.
 

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
Also a 6 pole motor at that rpm. I guess due to fitted to a band saw?
Usually star/delta connecting motors have the 6 terminals laid out 3 above one another.
Max.
yes, like the replacement one. I just thought the six wires might be used like the six terminals. the new motor was easy to reconfig to work with the VFD just move the terminal links and hook up to the VFD. then 230v and speed control. I wondered if i could use a meter to determine which of the six wires would be equivalent to the six terminals found in a dual star/delta motor. perhaps i should remove the end caps to see if there is a centre tap?
 

MisterBill2

Joined Jan 23, 2018
9,036
There is a good possibility the six wires are for configuring High or Low voltage, for example 240 or 480 Volts. Do you have the nameplate data for the motor? The nameplate data should tell you what you want to know.

Ron
I think that Ron is correct.
I recently replaced a 3 phase 2.2Kw motor on a bandsaw so that I could utilise a VFD for speed control. I thought that the original motor wouldnt switch between star and delta as it only had three connections. Looking closer I see that it has six wires coming out to the junction box. could these be reconfigured to make it useable with a VFD controller. If so how would I identify the correct wires?. any advice would be much appreciated. KeithView attachment 148030
And why did you consider that either star or delta windings were not suitable for use with a variable speed drive? I have used both with three phase drives, and they work.
 

MaxHeadRoom

Joined Jul 18, 2013
23,385
And why did you consider that either star or delta windings were not suitable for use with a variable speed drive? I have used both with three phase drives, and they work.
It appears to me the the OP was hoping to configure for 240v in order to run off of 1 phase residential.
Max.
 

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
I think that Ron is correct.

And why did you consider that either star or delta windings were not suitable for use with a variable speed drive? I have used both with three phase drives, and they work.
hello, thanks for your thoughts. I was hoping to use single phase 240 domestic mains to run the bandsaw with its original motor via a VFD.
I was told that if the 3 Phase motor didnt have the six links in its junction box to reconfig it to low voltage then it couldnt run off 240v even with a VFD.
I bought a new 3PH motor with the six links and was able to use it with the VFD very successfully. looking closer into the old motor as I am selling it, I noticed it has six wires coming from internally to its junction box. I thought these might equate to the six links. hence the query to more knowledgable people via this media. sorry for not explaining myself better originally. thanks again for the input.
 

Thread Starter

Keith Robinson

Joined Nov 30, 2014
53
I think that Ron is correct.

And why did you consider that either star or delta windings were not suitable for use with a variable speed drive? I have used both with three phase drives, and they work.
thank you for your input, perhaps Ive not made myself clear enough. please see my response to MrBill2. looks like the old motor wont work on single phase 240v whatever was done. Kind regards for your help.
 

MisterBill2

Joined Jan 23, 2018
9,036
It appears to me the the OP was hoping to configure for 240v in order to run off of 1 phase residential.
Max.
Using a VFD is an easy way to get the three phase power that the motor requires. The drives that I have used will work with a single phase input or 3-phase, although the max power out is reduced a bit. And a friend did that with a Bridgeport milling machine at his home shop.
 

shortbus

Joined Sep 30, 2009
8,727
Using a VFD is an easy way to get the three phase power that the motor requires. The drives that I have used will work with a single phase input or 3-phase, although the max power out is reduced a bit. And a friend did that with a Bridgeport milling machine at his home shop
As usual you don't read the whole thread. You seem to have missed what Les and the TS said.

As the motor looks like it was designed to run on 415 volts (Phase to phase.) in delta configuration if it was connected in star configuration it would require 719 volts phase to phase. Which would be 415 volts phase to neutral if there was a neutral.

Les.
So just how is a 220V VFD run a 415V motor?
 
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