Lafert ST63S4 Motor 1

[KeithCarrier]

I am a little confused about the 230/400V meaning of this motor. Does it mean that it is wired in a Delta or Wye configuration that uses 230V for startup and then switches to 400V once the motor has reached top speed. Or

Does it mean that I can configure the motor from 3 phase wiring to single phase wiring.

I think the former is correct, but can someone tell me for sure?

 

[waross]

Connect the motor in delta for use on 230V circuits.
Connect the motor in star for use on 400V circuits.
Three phase motors can not be reconnected for single phase.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[KeithCarrier]

Thanks Bill,

I understand now, for instance US is 230V 3 phase and Australia is 400V 3 phase. Is that correct?

 

[jraef]

Yes, in general. But in most countries where they have 400V available, it is 400Y/240V, so even there they can run the motor at 230V (although why is another question).

If you are using that motor in the US, understand that in general, 400Y/240V rated motors are designed for 50Hz operation. You can use them on 60Hz, but they will run 20% faster. If they are used on a pump or other centrifugal load, that increased speed may end up increasing the load on the motor beyond its design rating. You need careful consideration.

Also, you need to be concerned for the V/Hz ratio. You can run a 400V 50Hz motor at 480V 60Hz without issue (other than speed) because the V/Hz ratio s virtually the same. But not so at 240V. If the motor is designed for 240V 50Hz, the ratio is 4.8 V/Hz. So if you have 240V 60Hz power, you must increase the supply voltage to 288V (+-10%) or suffer a loss of torque. Less torque at higher speed = overload in most cases.


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[KeithCarrier]

Thak you jreaf, this has been most helpful.