squirrel cage induction motor 50 hz 60 hz
squirrel cage induction motor 50 hz 60 hz
Hi is there a difference between a 50 hz and a 60 hz motor can either be run on either frequency? I assume Ok as effectively that is what a VSD dose . But ..... ?
Re: squirrel cage induction motor 50 hz 60 hz
As you note, the underlying principle of VFDs is that RPM is proportional to frequency .
But that doesn't mean we can just mix-&-match.
Running a 50 Hz motor at 60 Hz amounts to a 20% increase in speed, which is significant.
Going the other way is approx 17 % reduction, again significant (and can cause problems when people import motorhomes from North America).
Running a motor at other than design frequency affects not only speed, but also power, torque and electrical efficiency.
And when running at less than design RPM, cooling efficiency is reduced.
All of this needs to be taken into account - I would be seeking expert advice before simply swapping-in a motor.
But that doesn't mean we can just mix-&-match.
Running a 50 Hz motor at 60 Hz amounts to a 20% increase in speed, which is significant.
Going the other way is approx 17 % reduction, again significant (and can cause problems when people import motorhomes from North America).
Running a motor at other than design frequency affects not only speed, but also power, torque and electrical efficiency.
And when running at less than design RPM, cooling efficiency is reduced.
All of this needs to be taken into account - I would be seeking expert advice before simply swapping-in a motor.
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Re: squirrel cage induction motor 50 hz 60 hz
Hi Guys,
I work on motors that are inherently controlled by VFD's (or VSD's, if you want to call them that).
Most of the stuff is pumps for liquids, if you go below 30Hz with any type of pump, it will not move any liquid and you have cavitation issues as well.
If however, you run a pump that is meant to run on 50Hz at a frequency of 60Hz, the output of that pump will be the square of the original output at 50Hz, if that makes sense.
So any restrictions you have will be made 4 times larger on the Discharge side of that pump.
Making a pump work harder into a given pipe size is going to kill the pump twice as quick.
I work on motors that are inherently controlled by VFD's (or VSD's, if you want to call them that).
Most of the stuff is pumps for liquids, if you go below 30Hz with any type of pump, it will not move any liquid and you have cavitation issues as well.
If however, you run a pump that is meant to run on 50Hz at a frequency of 60Hz, the output of that pump will be the square of the original output at 50Hz, if that makes sense.
So any restrictions you have will be made 4 times larger on the Discharge side of that pump.
Making a pump work harder into a given pipe size is going to kill the pump twice as quick.