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by zokier 492 days ago
> They were disposed to adopt 50 cycles, but American arc light carbons then available commercially did not give good results at that frequency and this was an important feature which led them to go higher

"The origins of 60-Hz as a power frequency" https://ieeexplore.ieee.org/document/628099

Better question is why did Germans pick 50 Hz, I'm not aware of any comparable benefits of having lower frequency

2 comments

If I read your source correctly, there is no real advantage of 60 Hertz or 50 Hertz, and the decision was usually due to circumstantial reasons, like supporting some existing arc-lights or difficulties with induction motors. Induction motors are also the reason why some railways chose to use 16⅔ Hertz, still in use to this day.

In the end, there is no real difference between 50 or 60 Hz, there is no clear advantage to either, especially with modern components. But you do have to choose as the whole network is synchronous.

How is better working lighting not a real advantage?
It would be, but that advantage was with very specific lamps that are now obsolete for more than 100 years.
50 Hz is a lot easier to math (50 Hz = 0.02/s, 60 Hz = 0.0166666). Don't know if that's why, but it very easily could be.
60 is the easier one, in that you can divide it by 3/4/6/12 and have an integer frequency. Probably the reason why a lot of Babylonian math used base 60, which is where our time and angle measurements come from.
60 is easier to factor, but that's kind of irrelevant when most AC formulas use frequency as a multiplicator. 0.02 is easier to multiply than 0.016667 (though at the end of the day, it doesnt really matter, because pi is used in most of the equations, so it ends up irrational anyway)
Pi (and e) are not only irrational numbers (not fractions) but also transcendental numbers (non-algebraic numbers meaning not roots of polynomials with rational coefficients).

So, even messier for dealing with than, say, square root of two (irrational and algebraic) or square root of minus one (algebraic).

> 60 is easier to factor, but that's kind of irrelevant when most AC formulas use frequency as a multiplicator.

Is the fact there are 360˚ (2π radians) in a circle, and 60 goes into that cleanly, of any use?

No really, because functions like sin(), cos() and tan() are defined numerically for "expecting Pi as input" rather than 360 degrees of angle.