Why did North America not use 220v

[badtlc]

Originally Posted By: jrustles
Originally Posted By: badtlc


But what do I know. I'm only an EE and design power distribution installations for everything from houses to refineries and power plants.


how do you feel about 'technical power' in homes; ie two hot 60V, where L1 and L2 of the split-phase system is always balanced.

Is there ANY advantage is eliminating current flow through the home's ground path?


I have never seen such an installation. Doesn't make any sense if they are still producing 120V source voltage. The current flow is the same regardless as long as voltage applied is the same magnitude. The current doesn't flow through the ground path, it flows through the neutral & hot conductors unless there is a ground fault.

 

[Papa Bear]

"So are you saying,
I could wire a European electric drill (for instance) connecting the drills Brown and Blue wires to the Black and Red North American 'Hots' use the Green and Yellow (ground) connected to the North American (Green) ground, and away I go??"


10-4. Make a jumper adaptor from dryer plug to euro plug that you can plug into the dryer receptacle when needed.

 

[exranger06]

Europe uses 50 Hz, North America uses 60 Hz. A drill designed for 50 Hz will not work well on 60 Hz frequency.

 

[badtlc]

Originally Posted By: exranger06
Europe uses 50 Hz, North America uses 60 Hz. A drill designed for 50 Hz will not work well on 60 Hz frequency.


Lots of devices will work fine on either. Depending on the type of device it can make zero difference or it can affect the output rating of the device. Devices designed for 60 Hz will see higher current magnitudes when they are on a 50 Hz system and vice versa.

Some devices will NOT work as you said, but there are many that will work fine.

 

[javacontour]

The 50 vs 60 hz thing hits a few things. When I lived in Germany, there was always some American GI who brought a clock from the US and wondered why it ran slow in Germany.

Even some digital clocks ran slow. It struck me as odd that they didn't have an oscillator independent of the AC input frequency.

I bought a digital clock radio that was made for 110 or 220, 50 or 60 Hz AC. Just flip the voltage switch on the bottom and you were good to go.

I had a Kenmore rolling dishwasher and a big transformer. That ran just fine on the 110v/50Hz the transformer supplied.

 

[Dave Sherman]

Originally Posted By: javacontour

Even some digital clocks ran slow. It struck me as odd that they didn't have an oscillator independent of the AC input frequency.


Must be a common thing, I have a digital clock with a battery backup that loses a few minutes each hour if the AC fails. Guess they figured since line frequency is very stable it didn't make sense to put a watch crystal in for the time base.

 

[Tony05]

Originally Posted By: friendly_jacek
Originally Posted By: friendly_jacek
I also always wondered why US outlets are way down near the floor level while the Euro standard is at your belt line more or less. No need to bend over to plug in/out, duh!


Is anyone going to answer this, or do I need to open a separate thread?


NEC has no real answer. There is a maximum height of 6' 7" or something similar. They go by wall footage. Even a floor receptacle next to the wall meets these requirements.

 

[Tony05]

Originally Posted By: Rick in PA
Another interesting outlet fact (if I have my facts correct) is that code requires an outlet every less than 12'. For approval (UL, ETL, etc.) a line cord has to be at least 6' long (some exceptions). Therefore you should be able to place a lamp or whatever anywhere without the use of an extension cord. At least I believe that's the theory.

Your are correct sir. It is written differently in the code book and get confused a lot by do it your selfers. They often put receptacles in every 6'.

 

[kschachn]

You are correct, you don't get 240v single phase in a residence of course. It seems like you already know the answer but the two hot legs are 120v to ground and are 180 degrees out of phase. So if you reference one against the other you get 240 volts.

Sort of like if one leg was +120v and the other was -120v DC. Either one is 120v with respect to ground but one against the other is 240v.

The best of both worlds IMHO. You get 120v for most needs plus the advantages of a higher voltage when needed.

Originally Posted By: expat
OK so educate me.

What wire gives me single phase 240v

I see a Red and a Black (hot) each read (a nominal) 120v
as I understand it, they are out of phase with each other.

Perhaps I'm wrong?

 

[PandaBear]

Originally Posted By: KenO
Basically, because Edison was a hard-core egomaniac, and a complete douchenugget. And tried to 1-up Tesla (and was usually wrong in the end, nearly every single time) at every chance he could.


Let me guess, you watched The Oatmeal's cartoon didn't you?

 

[Dave Sherman]

Originally Posted By: PandaBear
Originally Posted By: KenO
Basically, because Edison was a hard-core egomaniac, and a complete douchenugget. And tried to 1-up Tesla (and was usually wrong in the end, nearly every single time) at every chance he could.


Let me guess, you watched The Oatmeal's cartoon didn't you?


Whatever gave you that idea? Douchebaggery, I tell you.

 

[Pablo]

Originally Posted By: kschachn


The best of both worlds IMHO. You get 120v for most needs plus the advantages of a higher voltage when needed.



That's what I said above. The question is posed as if there is something wrong with this methodology. I contend it is actually smarter and gives the end user more choices. Again I pose the question how many new small devices used by the masses are inherently more efficient at 220 V?

 

[jrustles]

Originally Posted By: badtlc
The current doesn't flow through the ground path, it flows through the neutral & hot conductors unless there is a ground fault.


That's absolutely correct, I typed ground when I meant neutral, my mistake.

Under 'normal' circumstances, no current should flow through ground conductors, which are either bare wire or green sheathed.

About the technical power thing, I think some people like audiophiles etc create the systems to isolate the equipment power systems from earth noise. I don't know how substantiated it is, or how much it helps or if it's even worth it and wondered if you had any opinion on the issue


Originally Posted By: kschachn
You are correct, you don't get 240v single phase in a residence of course. It seems like you already know the answer but the two hot legs are 120v to ground and are 180 degrees out of phase.


Your dryer disagrees. How is 240v not the sum of L1 and L2 conductors

You mean to say that 240v, single phase exits the transformer and enters the premises with it's phase 'split' between the conductors, thus the name split-phase. A 120v, half-phase power system is fantastical! Splitting the transformer's secondary winding like that, at the center tap is how most 'pole top' transformers are configured. This allows, as we all know, 120v service out of a 240v transformer, with the help of the neutral center tap.

I suspect you understand that and, yes, it's funny to think of a split single phase 240v as two 120's, but the fact is that single, split-phase 240v service is still 240v service.

Quote:

So if you reference one against the other you get 240 volts.


Correct. This would be the service rating, 240v, the entire output voltage of the secondary coil in the transformer.

 

[expat]

Originally Posted By: Pablo
Originally Posted By: kschachn


The best of both worlds IMHO. You get 120v for most needs plus the advantages of a higher voltage when needed.



That's what I said above. The question is posed as if there is something wrong with this methodology. I contend it is actually smarter and gives the end user more choices. Again I pose the question how many new small devices used by the masses are inherently more efficient at 220 V?


Well I personally spend more time using power in the workshop than in the kitchen, or doing housework.
I do have 240v outlets in the workshop, and use them whenever I have a tool that draws a lot of power and is 240v or is convertible to 240v ie. my table saw, milling machine, old RA saw.
I would like to run my MIG welder on 240v but (in this country) 120v makes for a more portable machine.

In the kitchen, we have a wimp of an electric kettle as we are limited by the 120v 15amps available. Our vacuum cleaner also draws 15amp and runs hotter than it need.

People tell me you can't set up a decent grow Op on 120v

More and more 12 gauge wire is required by the electrical code presumably because of the resistance in drawing power through 14 gauge wire at 120v.

It just seems 240v is better and from a circuit overload standpoint (speaking as a layman here) it seems safer.

 

[kschachn]

OK, yes I was wrong and you are correct.

Same as in our business when you pick 208v off two legs, right? Although those aren't 180 degrees out.

Originally Posted By: jrustles
Your dryer disagrees. How is 240v not the sum of L1 and L2 conductors

You mean to say that 240v, single phase exits the transformer and enters the premises with it's phase 'split' between the conductors, thus the name split-phase. A 120v, half-phase power system is fantastical! Splitting the transformer's secondary winding like that, at the center tap is how most 'pole top' transformers are configured. This allows, as we all know, 120v service out of a 240v transformer, with the help of the neutral center tap.

I suspect you understand that and, yes, it's funny to think of a split single phase 240v as two 120's, but the fact is that single, split-phase 240v service is still 240v service.

 

[badtlc]

Originally Posted By: kschachn
You are correct, you don't get 240v single phase in a residence of course. It seems like you already know the answer but the two hot legs are 120v to ground and are 180 degrees out of phase. So if you reference one against the other you get 240 volts.



The service to your home is 240, single phase. If the 120v legs were 180 degrees out of phase, they would add up to 0. 120 at an angle of 0 plus 120 at an angle of 180 = 0.

 

[badtlc]

Originally Posted By: kschachn
OK, yes I was wrong and you are correct.

Same as in our business when you pick 208v off two legs, right? Although those aren't 180 degrees out.



Commercial will typically get 480V, 3-ph from the utility. From there, it is common to step down to 208, 3-phase for all low voltage loads and receptacles. The phase difference between each phase on 3-phase systems is 120 degrees (120 + 120 + 120 = 360 degrees for phasor math).

So, in commercial you have have 120V in 3 different phases (line to neutral) or you can have 3 different phases of 208V (line to line). So instead of 240V, in commercial settings larger items need to be rated for 208, 3-ph or 208 single phase. Welding receptacles can even be 480V, 3-phase.

 

[jrustles]

Originally Posted By: badtlc

If the 120v legs were 180 degrees out of phase, they would add up to 0. 120 at an angle of 0 plus 120 at an angle of 180 = 0.


I think he means voltage phase measured at each leg in immediate relation to the neutral center tap, which is the only way 120v can be measured anyway.

Surely you're correct if each 240 hot leg is 180 out from the other

 

[Dave Sherman]

Originally Posted By: badtlc
Originally Posted By: kschachn
You are correct, you don't get 240v single phase in a residence of course. It seems like you already know the answer but the two hot legs are 120v to ground and are 180 degrees out of phase. So if you reference one against the other you get 240 volts.



The service to your home is 240, single phase. If the 120v legs were 180 degrees out of phase, they would add up to 0. 120 at an angle of 0 plus 120 at an angle of 180 = 0.


Well, you're partly correct. Yes, you have 240 volt single phase coming to your house. However, if you look at each hot leg with respect to neutral, the two legs are 120 volts and they ARE 180 degrees out of phase with each other. If you could look at each leg with a two-channel oscilloscope referenced to neutral, you would see 120 VAC on one trace, the other would also be 120 VAC, but inverted (i.e., 180 degrees off) from the first.

 

[Vikas]

I thought the two legs were 120 degrees apart.