400Hz supplies; was: RK05 spindle pulleys - trade 50Hz vs 60Hz?

[Stefan Skoglund]

tor 2018-07-26 klockan 12:15 -0700 skrev Chuck Guzis via cctalk:
> On 07/26/2018 11:51 AM, Ed Sharpe wrote:
> > 
> > smecc has  stashed a  huge  mother gen  set    115  60cy  in  115
> > 400 cy  out. was used to  run    rca avq  10  raradr....
> > we  have....
> > but  could  run many   many things... it is  huge,,, these things
> > exist out there  if you need one,...
> 
> 400Hz power was also used in aviation gear.  I remember having a
> stock
> of small surplus 400Hz transformers salvaged from various bits of
> equipment purchased on Chicago's "Surplus Row".
> 
> Transformers are much smaller than their 50/60 Hz cousins.
> 
> On the other hand, when I worked in a steel mill, much of the power
> distribution was 25Hz.  Transformers were much larger.  At some
> point,
> one of the mills converted their lighting from incandescent to
> mercury-vapor running from that 25Hz supply.  I'm surprised that
> nobody
> experienced seizures from the flicker.
> 

The electric arc furnace works much better at 25 Hz.

The hydro power station in Trollhättan was first built as a 25 Hz
because :
desiredness of electric power for the metallurgical industry in
Trollhätan.
Trouble: the other intended customer Gothenburg city wanted 50 Hz.

The last 25 Hz generator in Trollhättan was taken off the electric grid
in 1959.