US power system

[John Williamson]

60Hz transformers are *exactly* the same efficiency as 50Hz transformers as long as each is run at its design frequency. 60Hz ones having a bit less steel (Due to the frequency) and a bit more copper (Due to the higher output current in the USA, as they use a lower final distribution voltage) is the only difference.

It means that in New York, if the power were fed from San Francisco, it would be about a cycle behind San Francisco, with a gradual phase change across that distance. In theory, you could use the grid in the USA as a resonant circuit at 60 Hz, which could make life "interesting".

Electricity is based on the charge on the electron. This isn't even an integer, unless you are *very* careful selecting the units.

[Uncle Peter]

Or maybe the core is loose or something? Doesn't make a noise though. It says 50Hz, made by TDC Power.

[Uncle Peter]

Er.... I asked a question. The very long post was mainly a quote from a website.

[Uncle Peter]

I guess the website I read about Tesla's 60Hz idea being optimal was somewhat misguided.

I assume they must have some phase matching systems somewhere?

But the frequency we choose will have an effect on the number of frames a second on TV, the speed of motors, etc, etc. And those things we like to be metric.

[Uncle Peter]

It's old. I don't think they make wall warts with transformers any more. Cheaper to make a little switched mode and save on the iron core, and postage!

[John Rumm]

I don't think its appropriate to call this two phase - split phase perhaps. Its basically a single phase supply transformer with a centre tap used as the neutral, giving a 110 - 0 - 110 supply.

[John Rumm]

Not if take in the context of the big argument between proponents of DC Vs AC power distribution systems. Tesla was pushing hard for the adoption of AC which ghe believed would be far more efficient than the DC systems.

[Uncle Peter]

Yes, but if you had a two phase generator, is that not exactly the same as what you'd see? A phase 180 degrees out is the same as the other end of a centre tap.

[Uncle Peter]

It's a lot cheaper to change the voltage of is it not? (For HV long distance power lines). Although I notice the Japanese have HV DC lines?!

[Uncle Peter]

Indeed!

Time ain't metric.

Fuel type. I buy nuclear as it's cheaper.

There are too many people per square foot in the UK.

[John Williamson]

Do you have you own personal reactor, then?

All the companies which supply the consumer buy their power from the same pool of conventional, nuclear and renewable. If they tell you anything else, it's because they say things in the small print like "We buy enough per year from X source to cover all our clients' use."

So the Green tariff I was on a while ago bought enough energy from renewable sources to cover my annual use, but the power was still generated by the standard mix.

You got that right. Too many Fast Breeders...

[charles]

or more often thought of as 5 shillings, for which there were individual coins, too.

[whisky-dave]

Oi you leave immigration out of this ;-)

[David Paste]

I think that only really applied when TV was analogue. Now everything is digital, you can have whatever you want.

[Dave Plowman (News)]

It only really applied when analogue TV was mains locked - and that practice ceased IIRC over 50 years ago.

[charles]

The studio lighting, unless dc driven, neads to have the same frequency (to a first order) as the tv system. A serious 10Hz beat can happen if not.

[Dave Plowman (News)]

Studio lighting was all tungsten at one time. And I doubt a 5000 watt lamp is going to flicker much. ;-)

[charles]

It certainly did it with halogen lamps.

[John Rumm]

If your taking (any) two phases from a 3 phase distribution network though, they won't be 180 degrees out of phase...

[Uncle Peter]

If 80% of a power company's customers select green, and 20% select coal, they should be buying that ratio of power. If not, then they're charging the green customers extra money and pocketing it, which is theft.

ROFL!