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Re: [ARSCLIST] Odd Speed



----- Original Message -----
From: "Mike Richter" <mrichter@xxxxxxx>

> At 03:05 PM 3/5/2004 -0500, Steven C. Barr wrote:
>
> >Aren't all the electrical systems in North America synchonized at an
exact
> >60Hz, in order to avoid various spectacular results when they are
> >interconnected
> >(which is often the case)? I have ni idea how this is done, but I think
I've
> >been told it was/is done...
> >Steven C. Barr
>
> They are not precisely synchronized. However, at least in the U.S. there
is
> an adjustment each night to ensure that precisely 60x60x60x24 cycles
> transpired since the last one.
>
> Precise synchronizatin is not possible since the signals pass along wires.
> They travel at about the speed of light in vacuo, but even so if they are
> in phase at one point of the grid they are out of phase at another
> junction. Think of it as one grid being U-shaped between two nodes and
> another grid connecting at those same nodes being straight. While the
> result might be a phase error of only a fraction of a degree, the
> connections cannot depend on the signals being in phase or even precisely
> at the same frequency.
>
> Though all that was explained to me by someone who knew, I did not have
the
> sense to ask how the tricks were pulled off.
>
Hmm-m-m-m...kinda makes sense, but let me see. I'll do this in meters to
make
the math easier (besides, as a Canadian I have to!)...

Electicity travels at approximately 3*10^8 meters/sec (300,000,000).
This means if the paths were different in length by 300 km (300, 000 or
3*10^5 m) there would be a difference of 1 millisecond. This puts the
two waveforms out of perefect sync by one part in a thousand...or
.36 of a degree (assuming the generators were in sync).

Will this have any effect on AC devices?
...stevenc


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