Run 50Hz motor on 60Hz

[CMCarter01]

Greetings:
Simple Question ...
I have to install a mist collector with a 380/50/3 motor on a machine which will supply 400/60/3 power to the motor.
I don't thing this will cause a problem with the motor since I will be increasing both the voltage and the Hz but I would like the opinions of some people that are more experienced then I am in this field.
Thanks,
Spike

 

[winnie]

The general _approximate_ rule for induction motors is to maintain 'constant V/Hz'. Thus a motor rated at 380V and 50Hz would ideally be operated at 456V and 60Hz. This will result in proper magnetic field strength, and let the motor develop full torque.

However the motor will also run 20% faster, which can substantially increase the torque demanded by the load. The motor will also have higher locked rotor current and most likely lower locked rotor torque, which could mean that the motor might not properly start the load.

You will be running the motor below proper voltage for the frequency. This will reduce starting torque. Once running, because the voltage is low, the current consumed by the motor at full load will be _greater_.

Most motors have a voltage _range_ over which they can be reasonably used.

You will need to evaluate the load characteristics and find out the voltage _range_ capabilities of the motor in question.

-Jon

 

[robbietan]

if the motor is part of a process, the increased speed due to 60Hz may affect the process. 380/400 is still with the -10% voltage motors can run.

 

[boater bill]

What is the Motor frame on the motor in question? Can you easily replace it with an appropriate 60Hz. unit?

 

[winnie]

if the motor is part of a process, the increased speed due to 60Hz may affect the process. 380/400 is still with the -10% voltage motors can run.

I get that 400V is -12%, presuming that 380V is the actual design voltage.

Remember that there is a change in frequency, so the 380V at 50Hz maps to 456V at 60Hz, and 400V is 12% below 456V.

-Jon

 

[CMCarter01]

Thanks for the input

Thanks for the input

Thanks for the input.
I might just install a small step-up transformer and use a standard 460/60/3/ motor.
Spike

 

[GeorgeB]

Greetings:
Simple Question ...
I have to install a mist collector with a 380/50/3 motor on a machine which will supply 400/60/3 power to the motor.

400/60/3 is an unusual supply ... are you sure.

Many motors I run into on European machinery are dual rated 380/3/50 and 460/3/60. The other answers you received on torque and speed are, IMO, accurate. Do not count on 6/5 (1.2) increase in HP as the motor thermal limits will probably get you first.

If you really need the 50 Hz, and really have 400V, consider an inverter; depending on the motor size, it may be economical. (Another issue is that "most" motors over 5kW on European machinery seem to be wye/delta start. If you consider a new motor, check the starter.

 

[iwire]

400/60/3 is an unusual supply ...

Not so unusual, a lot of the equipment where I am working now requires 400/60/3.

Next week I will be installing two 93 kVA 480 to 400 transformers to supply two new pieces of equipment.

 

[robbietan]

I get that 400V is -12%, presuming that 380V is the actual design voltage.

Remember that there is a change in frequency, so the 380V at 50Hz maps to 456V at 60Hz, and 400V is 12% below 456V


Yes, I was operating under the illusion that the freq. will still be 50Hz. thanks sir.