In 030622 MMDigest Robbie asked:
>[ What is available for (1) consumer devices of 50-200 watts that
>[ accept 50-60 Hz mains frequency, and (2) orchestrions powered with
>[ antique 230 VAC 50 Hz fractional horsepower repulsion or induction
>[ motors? -- Robbie
A point worth mentioning is the frequency. Canada runs on 60 Hz,
but many systems around the world run at 50 Hz. Induction motors spin
just under their synchronous speed. If you attempt to run them under
conditions for which they were not intended, the motor will generally
work fine, but the load it sees is another matter.
Fan loads, in particular, vary with the cube of the speed they run.
Running a fan on 60 Hz current that is intended to run at 50 Hz will
result in an increase of 73% in the motor load. Fans that are run by
belts can use replacement drive parts to correct this. Fans that are
direct drive are a little more difficult to deal with.
Going the other way, running a fan on 50 Hz that was designed to run
at 60 Hz will result in a reduction of pressure and volume of air
delivered, but the motor will generally work fine.
Don Shenbarger
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