60 Hz Electrical System

[Besoeker]

But what advantage does that really have?

Oh, the absolutely enormous, gigantic, and humongous advantage in that you can express the period without having a messy, ever recurring decimal fraction...........

 

[ActionDave]

Not at all user friendly. Just efficient for long distance transmission, can be produced by low shaft speed generators without an obnoxious number of poles and also does not produce annoying flicker from an incandescent light.

Why the "Not at all user friendly"? Seems like the perfect frequency for a clock.

 

[GoldDigger]

But it the worst possible frequency for disrupting your heart and killing you. I call that darn unfriendly.
And any integral number of cycles per second will be fine for a click for most uses. If you are interested in sub-second time units 50Hz would arguably be better than 60Hz.

 

[Besoeker]

Why the "Not at all user friendly"? Seems like the perfect frequency for a clock.

Most clocks, in my experience anyway, now operate from a quartz crystal rather mains frequency.

 

[romex jockey]

In truth it is an engineering compromise between motor speed, system loses, raw material and so forth.

An apt reply,thx Mr MBrooke......, would you know if N. Tesla had anything to do with this?

For example, 400 Hz would make for some very small and light weight transformer. This alone would make 60Hz look very impractical, and its actually why its used on aircraft where weight is of great concern. However at 400Hz conductor skin effect goes up which increases transmission line losses to the point of impractical when compared to lower frequency. A 400Hz motor is to fast even with the minimum number of poles for most applications, so yet again a lower frequency is desired. The frequency cant be to low either as iron and copper material required offsets any reduced transmission losses.

I've always wondered about that too .

Theoretically , a certain level of higher HZ 'skin effect' might result in more electrons flowing around the skin of a conductor,possibly in an EMF field, than through it ...?

~RJ~

 

[mbrooke]

Oh, the absolutely enormous, gigantic, and humongous advantage in that you can express the period without having a messy, ever recurring decimal fraction...........

True, but how often does this decimal get used?

 

[mbrooke]

An apt reply,thx Mr MBrooke......, would you know if N. Tesla had anything to do with this?

From what Ive read he was the one that decided on 60Hz as an optimal compromise. There was 16Hz, 25 Hz, 40Hz, 50, 60, 133Hz ect, ect all of which were delaying the current grid in some way or another. I have a really good paper that I will PM over.

I've always wondered about that too .

Theoretically , a certain level of higher HZ 'skin effect' might result in more electrons flowing around the skin of a conductor,possibly in an EMF field, than through it ...?

~RJ~

Correct, more electrons will be driven closer to the surface which means less power transmitted for the same conductor. Also, line charging currents go up. The higher the frequency the more power goes through a capacitor which means conductors having capactive coupling with anything will pull more current for that alone. Long distance AC lines become very expensive if not impossible with higher frequency.

 

[Besoeker]

True, but how often does this decimal get used?

I think you missed the intended wit. Never mind.

Slightly more seriously, one example is the calculation of RMS values.

 

[iceworm]

Why the "Not at all user friendly"? Seems like the perfect frequency for a clock.

Going back to 1970s, working for Simplex Time Recorder Co:
All had an iron core with a 120V coil and copper loop to make the field sweep. The core had a hole that fit a little sealed can with a six pole reluctance rotor and a gear train, shaft sticking out one end.

Take a 1200rpm rotor and turn it down 1200:1 to make the second hand move the right speed

or

Excite the coil with 50 Hz, and gear it down 1000:1

Not seeing much difference there.:?

ice

 

[iceworm]

Oh, the absolutely enormous, gigantic, and humongous advantage in that you can express the period without having a messy, ever recurring decimal fraction...........

True, but how often does this decimal get used?

I think you missed the intended wit. Never mind.

Slightly more seriously, one example is the calculation of RMS values.

Bes is correct - some wit intended. But more than half

Now for a bit more serious:
For a lot of calculations one uses radians/sec. For 60 Hz the common used value is 377. Error is .003%.
I don't know what number the 50Hz crowd uses, maybe 314. that would have an error of .05%

Neither one are even or rational numbers. Not much difference there.

ice

 

[ActionDave]

Going back to 1970s, working for Simplex Time Recorder Co:
All had an iron core with a 120V coil and copper loop to make the field sweep. The core had a hole that fit a little sealed can with a six pole reluctance rotor and a gear train, shaft sticking out one end.

Take a 1200rpm rotor and turn it down 1200:1 to make the second hand move the right speed

or

Excite the coil with 50 Hz, and gear it down 1000:1

Not seeing much difference there.:?

ice

60 seconds, 60Htz, 60 goes into 360 evenly, 50 doesn't. That's what I was thinking about.

Also, overall I'm happier with numbers that can be divided evenly into thirds. That is the #1 reason I don't like the metric system.

 

[iceworm]

60 seconds, 60Htz, 60 goes into 360 evenly, 50 doesn't. That's what I was thinking about.

Also, overall I'm happier with numbers that can be divided evenly into thirds. That is the #1 reason I don't like the metric system.

Yeah, I was pretty sure that was what you thought - and I'm okay. Not even jerking your chain, just twitching it a bit - about where we get stuck cause that was the way our grandads did it.

And you are right about the "thirds". Look how stuff is packed for shipping: Dozens come up plenty; cases of 24, ...

ice