415V/720V 3 Phase Motor Query

[Wendelspanswick]

My universal woodworking machine has 3 seperate 5.5kw electric motors which I power with a Transwave 415V static converter which works fine but I am curious as the labels on the motors show 415V or 720V rather than the 240V or 415V that you normally see?
I understand that in the UK 3 phase is 240V per phase measured to neutral and 415V when measured across any 2 phases.
How would the windings be configured in the motor to get 720V across the windings?
Curiosity value only!

 

[piman]

Hello Weldspamwic,

it's not the windings that give the voltage, rather the voltage applied to the motor requires the star or delta connection. In this case the motor has 415 volts per phase winding so (415 x 1.732 = 720) used in star.

Alec

 

[Wendelspanswick]

That sounds logical but where do you find sites with a line voltage of 415V measured to neutral?

 

[piman]

Hello Wendelspanwick,

I can't answer that, I believe mines used higher voltages but I don't know for certain. If you want to use that motor you can only practically use it at 415v.

Alec

 

[Wendelspanswick]

It's an SCM machine, made in Italy I think so perhaps some European countries use a 415v line voltage.
The way the machine is set up is with a manual Star Delta system via rotary switches on the front panel.

 

[arther dailey]

I rewound thousands of motors back in the day, 110 volt, 240 volt, 415 volt 3 phase and the nice ones 3.3k 3 phase, never saw a 700 odd volt ever, so yes a strange one but piman is correct in what he explained.
also did transformers solanoid coils armatures etc etc, but a rubbish industry as everything is a rush job ! arther

 

[wheresmejumper]

Think Canada has 3 phase 575v

 

[arther dailey]

didnt know canada was 575v, so whats there household stuff 110/120?

 

[MCKDAVID]

690v was common in the marine industry, but I've never head of 720v

 

[wheresmejumper]

didnt know canada was 575v, so whats there household stuff 110/120?

I don't know.just have seen a few lincoln welders that were 575v only,for Canadian market.