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Einar Ágústsson
02-02-2008, 12:06 AM
Is it possible to use equipmet maked for 3 phase

460V 60Hz where the power supply is

3 phase 400V 50 Hz

Does it have more impact on the control device then

on the motors

wambat
02-02-2008, 02:25 AM
If a motor is to be used with a different power supply voltage than specified, a transformer must be connected between the power supply and the motor. The
primary winding of the transformer should be of the same voltage as the power source, and the secondary winding
voltage should be the same as the voltage rating of the motor or fan.
The transformer should be rated for a current of at least twice the rated motor
current to allow for the current peak at motor start. The transformer should also
possess stable transforming characteristics. Also the motor will run about 15% slower then it's rated RPM at 60 HZ :)

smpsmp45
02-02-2008, 08:01 AM
We did face similar problems in Saudi wherein the power supply did vary from site to site.

We did all the experimentation & finally started buying motors from Europe if the Power used to be 50 HZ supply.

nike123
02-02-2008, 09:13 AM
What kind of equipment?

tedre
03-02-2008, 05:09 AM
Hi I'm new to RE. Nice meeting you guys.

It is big possibility to use in Europe. But you have to check name plate first or contact manufacture.
Many condensing unit and compressors are rated at 460/3/60 and 380-415/3/50. You can not use same voltage with 50 hz. Motor will overheat.

Tedre:)

Electrocoolman
04-02-2008, 02:22 AM
Hi. reducing the frequency of the supply will reduce the speed of the motor, which in turn will reduce the back emf generated by the motor. This lower back emf (which opposes the supply voltage) means that a higher voltage is applied to the windings, thus an increased current flows in the windings.
It is therefore necessary to reduce the supply voltage applied to the motor so that the current is still within the limits of the motor. Remember P=I*I*R (heat is square law of current) so this stops motor overheating. As the motor is also running slower the cooling fan is less effective and airflow reduced...thus cooling less effective.
As less power can be supplied to motor, the motor h.p. rating is also reduced.
Variable speed drives use a Voltage / Frequency curve to control the votage applied to the motor to keep the current in limits.
Transformers (as Wambat suggested) will not work as frequency and voltage are the key factors
Hope this gives you an insight and helps.
ECM.