4 Wire Wye Vs 4 Wire Delta - New Construction

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mbrooke

Batteries Included
Location
United States
Occupation
Technician
Yes, they do. Is 150 years your anticipated time frame?


Might be. But, to be honest I dont know much about how this issue will be solved. I dont know what DC sockets will look like.

The rating and number of conductors comes into it too.

True and that has been considered, even patents exist. First two buss bars will be used over 3 in a bipolar system. Second existing AC lines will either operate as 3 circuits, one circuit with 3 paralleled conductors or in the case of a single circuit AC line: the center phase will either by cycled in relation to the two other conductors to let them cool briefly (to prevent over temperature) or the center phase will simply be a spare. Let me see if I can find the patents to that.




How exactly would you implement that?

Galvanic isolation for power transfer and opti coupler for both firing and information transfer.


And fit DC rated switchgear.

My point being its not like all current equipment is AC in a DC conversion will force inverters into every appliance.
I'm not suggesting that it would. A light bulb wouldn't

Which will be either retrofitting existing gear, or new gear as old gear is replaced. 600 volt and under DC will be phased in over decades, not at once.


Norway is over 90% renewable - and AC.

And how is Norway linking with other girds? :)
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
Thats my point, you can not discredit my views or say otherwise. Yes I can not speak for every school on earth, but I can speak from my experiences.

Precisely. When you said that most educators deserved to be in prison and should not be around kids you are extrapolating your personal experiences to every school on earth, which is ridiculous. If that were true, in my experience in the public school system and with three institutions of higher learning, statistically speaking I would have had to have run into at least some of that. I didn't. I did not encounter a single professor who... how did you put it? "People who have no clue that they have no clue. They denigrate, belittle and ridicule the very people who created all the luxury that surrounds them which they have to yet fully appreciate." Yeah, that's it. Not a single teacher or professor I encountered was even remotely like that.

Of course I cannot dispute your experiences; I don't know you or what you ran into in schools you attended, but frankly what you said sounds merely like the parroting of rhetoric to me.
Explain :?
Irony needs no explanation.

I never said they were universal..
But yes, you did, which is exactly my point.

As time moves on, that iron will have to be replaced. Equipment will be replaced no matter what it is made out of. An example are pole mounted distribution and substation transformers. The majority of those installed in the 30s and 40s have already been replaced. Where I live entire surrounding towns had 4.8kv delta and 4.16kv Y distribution only to upgraded with 13.8kv Y in the last 10 years. The cost was huge, you bet, but 60+ year old equipment had enough.

Was any of that equipment DC? No. It was replaced, but what it was replaced with had to be compatible with the rest of the existing grid, and that "huge" cost was less than a particle of a pittance compared to what replacing the AC grid with DC would cost. What you are proposing is a wholesale replacement of the entire grid infrastructure. Forget about the cost for a moment; think about the pain of either having two incompatible systems running at once, or having to shut the whole grid down for the time it takes to replace all that hardware. It isn't going to happen any time soon, maybe never. Whether or not it would ultimately be a better system just isn't that relevant.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Precisely. When you said that most educators deserved to be in prison and should not be around kids you are extrapolating your personal experiences to every school on earth, which is ridiculous.

Or more the US public education system.



If that were true, in my experience in the public school system and with three institutions of higher learning, statistically speaking I would have had to have run into at least some of that. I didn't.

As I said, just because it worked for you does not mean it works for everyone.

I did not encounter a single professor who... how did you put it? "People who have no clue that they have no clue. They denigrate, belittle and ridicule the very people who created all the luxury that surrounds them which they have to yet fully appreciate." Yeah, that's it. Not a single teacher or professor I encountered was even remotely like that.

Which does not mean they do not behave that way toward others or all teachers act like yours did.


Of course I cannot dispute your experiences; I don't know you or what you ran into in schools you attended, but frankly what you said sounds merely like the parroting of rhetoric to me.

If the US education system was really worth something FAPE would apply to everyone. A one size fits all would not exist either.



Irony needs no explanation.

Explain, I genuine dont understand.

But yes, you did, which is exactly my point.

In some ways what I said holds water across the board. Google where US public education ranks when compared to the rest of the world and tell me why that might be. Tell me, why does it sit where it does if my experience was the only one.

Was any of that equipment DC? No. It was replaced, but what it was replaced with had to be compatible with the rest of the existing grid,

In fact it was not compatible. A 7.5kv transformer can not go on a 2.4kv grid. The entire distribution system and substation went from 4.16kv to 13.8kv. Price it out, it was not free.



and that "huge" cost was less than a particle of a pittance compared to what replacing the AC grid with DC would cost.

Today, tomorrow might be different.

What you are proposing is a wholesale replacement of the entire grid infrastructure. Forget about the cost for a moment; think about the pain of either having two incompatible systems running at once, or having to shut the whole grid down for the time it takes to replace all that hardware. It isn't going to happen any time soon, maybe never. Whether or not it would ultimately be a better system just isn't that relevant.


Wont happen. The change over will occur as equipment fails. This has occurred countless times all over the world and in the US. At one point 69kv was the dominant transmission voltage, it is now 115 and 138kv. How did they do that involving thousands of substations, lines and transformer?

Keep in mind these converters will take it into account. One day running DC to AC the next DC to DC.
 

tom baker

First Chief Moderator
Staff member
Many motors are dual voltage rated IE 200-230.
A motor for a 208 Y is rated 200 V
A motor for a 240 volt system is rated 230V.
Its a code violation to use a motor rated 200 V on a 240 volt system and use a 230 V motor on a 208 volt system. Not only that but a motor has a 10 % voltage tolerance, low voltage to the motor results in more current and high voltage results in the windings being saturated and the current going up.
Our POCO does not offer a 120/240 mid point grounded delta system.
 

kwired

Electron manager
Location
NE Nebraska
Many motors are dual voltage rated IE 200-230.
A motor for a 208 Y is rated 200 V
A motor for a 240 volt system is rated 230V.
Its a code violation to use a motor rated 200 V on a 240 volt system and use a 230 V motor on a 208 volt system. Not only that but a motor has a 10 % voltage tolerance, low voltage to the motor results in more current and high voltage results in the windings being saturated and the current going up.
Our POCO does not offer a 120/240 mid point grounded delta system.
What? you want to get back on topic?:)
 
Location
Australia
The stinger is a big problem for the untrained and utilities don't like bad PR. Plus utilities are big business and big businesses like simple, one size fit all as often as possible.
 
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