Vic Rosenthal wrote:
>
>> ARNE GJERNING wrote:
>>
>> The other question is the concern of 50Hz vs 60Hz. Any problems here or
>> precautions needed.
>
>I built a 3300v power supply with the intent to use it in a 50 Hz country as
>well as here in the US. I asked Peter Dahl about this. I was told that the
>magnetizing current in the primary of a large 60 Hz transformer operating on 50
>Hz would be excessive, enough to burn it out. Much more iron is needed in a 50
>Hz transformer -- the one I finally got weighed 60 pounds (27kg), compared to
>an
>equivalent 60 Hz only unit weighing 40 pounds (18 kg).
Interesting figures... so the total weight of the transformer increases
as something like the square of the core cross-sectional area. Seems
about right.
And then the capacity of a blower with an AC induction motor DEcreases
with about the square of the mains frequency. It's small wonder that so
much "50/60Hz" equipment is sweating when operated on 50Hz.
I wonder how many developers in the 60Hz hemisphere actually have the
capability to test equipment at significant power on 50Hz?
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.com/g3sek
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