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That websites formatting is trash.

Archive: https://archive.today/4msz6

From the post:

>I would like to start on September 8th, 1878. That was when 31-year-old Thomas Edison was brought by a friend to see an inventor named William Wallace who, with a collaborator named Moses Farmer had made a special DC generator (or dynamo) that could light 8 very bright lamps at a time called “arc-lamps”.

That websites formatting is trash. Archive: https://archive.today/4msz6 From the post: >>I would like to start on September 8th, 1878. That was when 31-year-old Thomas Edison was brought by a friend to see an inventor named William Wallace who, with a collaborator named Moses Farmer had made a special DC generator (or dynamo) that could light 8 very bright lamps at a time called “arc-lamps”.

(post is archived)

[–] • 4 pts

I hate to break it to people, but the United states actually does use 220 volts like the rest of the world.

The 110 volts, everyone loves, is what is known as split phase 220. That is, a home typically uses and has 220 volts. However, you get, as a bonus 110 volts due to the 3rd line, which is connected to the transformer's center tap. Your circuit breaker panel is designed to use the center tap as "neutral" and most breakers use the center tap and one of the outer lines as 110 volts. Then the breaker panel also has the opposite line and the center tap, giving 110 volts in the reverse phase.

[–] • 3 pts

Yeah, how do people think they get a 220v plug for a washer/dryer or for a hottub or something? Its not just a magic box they attach to your breaker box.

[–] • 2 pts

I hate to break it to people, but the United states actually does use 220 volts like the rest of the world.

Came here to say this.

[–] • 4 pts

The bigger question is why much of the world uses 50 Hz AC instead of 60 Hz AC which better relates to timekeeping.

[–] • 3 pts

25Hz Forever

[–] • 2 pts

You think way too high: zero Hz forever.

I'm actually being serious. There's now the idea of HVDC lines coming out. I think this is a great idea, actually because you can drastically lower the amount of copper by eliminating the third line in 3 phase. The lower diameter wire can be used because DC current can flow through the whole wire, as opposed to the skin effect of A/C. Not to mention that the nasty power factor problem goes away.

[–] • 2 pts (edited )

You mean the third line in split phase? 3 phase often has 4, 3 phases and a neutral (Wye configuration, Delta doesn't.) You also need a safety for 5 wires.

You technically only need two wires coming in for residential, the transformer can split the phase at the final distribution point.

Skin effect at 60Hz isn't that much of a problem. Your biggest problem is going to be the massive losses of the DC system (AC is theoretically sum-zero) and the problem of getting it down to a useful voltage that isn't thousands of volts. AC is why Westinghouse's system worked for distribution and Edison's didn't.

If we really wanted to do it right, we'd all go to 400Hz and be like the military.

[–] • 1 pt

Well, I keep hearing that power factor is a big problem and there are plenty of circuits to correct that. If it wasn't such a problem, there would be no need to correct for power factor loses. I admit, that residential use probably doesn't care about power factor loss that much.

DC losses are only at low voltages. If you bump DC up to say 300KV, the losses are a lot less than a few hundred of volts. In my own home, I use 48 volt DC primarily for my inverters. This seems to be convenient. My solar panels output about 120 volts DC (I string a bunch of them in series). I wanted to run lower gauge wire.

Now there are conversion losses from going to A/C. But for long haul power transmission, I think HVDC is the way to go.