Mains transformer weights

[Cydrome Leader]

Sjouke Burry <s@b> wrote:

"Jim Hawkins" <jimhawkins@manx.net> wrote in
news:uZ6dnX1KQIiQTIfSnZ2dnUVZ8nCdnZ2d@supernews.com:

Jim Hawkins wrote:
Is a mains transformer designed for 60Hz significantly lighter than
one of the same VA rating designed for 50Hz ?

Jim Hawkins

Following on from this, why is it that electricity generation is
limited to such low frequencies as 50 or 60 Hz ?
As the frequency rises, the energy lost through electromagnetic
radiation from the wires rises, but is it really a significant amount
? Would it be significant at 1 kHz ? If not, why isn't generation
done at that sort of frequency ? The savings in transformer weights
and sizes everywhere would be enormous. Is it because of mechanical
engineering limitations on the rotational speeds of the large rotary
generators the power stations use ?




I have worked in the airforce, they also used 400 Hz
on(or under) the ground.
You could hear the 3rth harmonic(1200 Hz) all over the
place, wich is not such a good idea in your home.
Very iritating for new workers, old workers had a
measurable dip in their hearing curve, and could not
hear that frequency anymore.Permanent damage.

Apparently they had line frequencies as 16.66 Hz and other strange stuff
like 25Hz, which was last used in the US for railway lines.

Here's a little about this:

http://www.nycsubway.org/articles/rotary_converter.html

 

[josephkk]

On 26 Jan 2012 23:50:39 GMT, Sjouke Burry <s@b> wrote:

"Jim Hawkins" <jimhawkins@manx.net> wrote in
news:uZ6dnX1KQIiQTIfSnZ2dnUVZ8nCdnZ2d@supernews.com:

Jim Hawkins wrote:
Is a mains transformer designed for 60Hz significantly lighter than
one of the same VA rating designed for 50Hz ?

Jim Hawkins

Following on from this, why is it that electricity generation is
limited to such low frequencies as 50 or 60 Hz ?
As the frequency rises, the energy lost through electromagnetic
radiation from the wires rises, but is it really a significant amount
? Would it be significant at 1 kHz ? If not, why isn't generation
done at that sort of frequency ? The savings in transformer weights
and sizes everywhere would be enormous. Is it because of mechanical
engineering limitations on the rotational speeds of the large rotary
generators the power stations use ?




I have worked in the airforce, they also used 400 Hz
on(or under) the ground.
You could hear the 3rth harmonic(1200 Hz) all over the
place, wich is not such a good idea in your home.
Very iritating for new workers, old workers had a
measurable dip in their hearing curve, and could not
hear that frequency anymore.Permanent damage.

I had dips at 2400 and 4800 Hz as well as 1200 when i was done with the
navy.

?-)