[Lowfer] [Other] History AC

[Ed Phillips]

Peter Barick wrote:
> 
> In the AC power industry, does anyone know a source of info on how 60Hz
> came about in U.S., contrasted w/ say 50Hz elsewhere?
> 
> I've also seen where in Quebec 16 2/3Hz was used industrially. Purpose
> of this?
> 
> Peter

	There have been a number of frequencies used, including 133 cps and 0
(DC).  I would assume 60 Hz became more popular when transformer "iron"
got less lossy and the higher frequency required substantially less
iron.  When I moved to Southern California in 1947 the Edison company
was in the process of converting from 50 Hz to 60 Hz, a big project
since they paid the bill of necessary conversions.  When my brother in
law got out of college his first job was working for Bechtel and
engineering conversions for industrial installations.  Changes included
"re-poling" of big motors and replacing small ones for which that wasn't
practical.  In addition it was necessary to change gear or pulley ratios
where speed was critical.

	Couple of anecdotes.  I remember going into a drug store in
Philadelphia (about 1946) and seeing a pinball machine with a DC to AC
rotary converter sitting under it.  This particular part of Philly was
still using DC that late.  When I fired up a home made TV set with a
fancy power transformer I'd gotten bootlegged at NRL it ran for a while,
smoked, and kept on smoking for hours.  The transformer was designed for
60 Hz with a hypersil core with pretty sharp saturation characteristics
and the 50 Hz had overheated the windings beyond redemption.

	The 16-2/3 Hz was (and maybe still is?) used for electric RR
locomotives which used series connected commutator motors because of
their speed-torque properties.  This frequency was "almost as good as"
DC and easier to transmit long distances.  

Ed

Ed