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#128596 - 07/01/03 02:20 AM 3 phase power
james S Offline
Member
Registered: 05/13/03
Posts: 102
Loc: West England
Iknow the power calculation for three phase delta or star is
p=3VL*IL*PF

(with the three sqaure rooted)
but why is it sqaure rooted and not cube rooted given that there is three coils or three spaces between the coils?or is this used for the time loss between each coil?

also if anyone knows how to express the correct symbol for sqaure rooted would be much appreciated!
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#128597 - 07/01/03 07:01 AM Re: 3 phase power
Bjarney Offline
Moderator
Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Don't know of a way to display the root symbol in "ubb code" for this site.



As for why root 3, check your library for basic AC power-systems texts.
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#128598 - 07/01/03 07:02 PM Re: 3 phase power
Ron Offline
Member
Registered: 03/13/02
Posts: 577
Loc: White Plains, NY
The "root 3" comes from the vectorial addition of (2) phase to neutral voltages which are 120 degrees out of phase with each other.
You'll have to dig out your (mine too) old high school physics book to prove it to yourself.

[This message has been edited by Ron (edited 07-01-2003).]
_________________________
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#128599 - 07/01/03 08:34 PM Re: 3 phase power
ThinkGood Offline
Member
Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
√
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#128600 - 07/01/03 09:54 PM Re: 3 phase power
Bjarney Offline
Moderator
Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
ã ã ã ã

TG -- You have the magic touch. Mine blow up.




[This message has been edited by Bjarney (edited 07-02-2003).]
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#128601 - 07/02/03 06:37 AM Re: 3 phase power
ThinkGood Offline
Member
Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
The way to display it is to use the "character entity" in HTML, which is &#8730&#059; -- that's ampersand, number sign, 8, 7, 3, 0, semicolon.

So you would type 2√ in your message to display 2ã

Hope that helps.

Edit: It was fun figuring out how to get the message to show &#8730&#059; rather than √

[This message has been edited by ThinkGood (edited 07-02-2003).]
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#128602 - 07/02/03 07:46 AM Re: 3 phase power
Bjarney Offline
Moderator
Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
Amazing, TG. Thanks.

I'd hit a brick wall with alt-251, but that's from the ancient days of "Wordstar".

You can learn something new every day. First it's these crazy computers. Then, that insane internet, to boot.
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#128603 - 07/02/03 06:35 PM Re: 3 phase power
ThinkGood Offline
Member
Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
Quote:
So you would type 2√ in your message to display 2ã

I have no idea what happened to that line
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#128604 - 08/23/03 06:07 PM Re: 3 phase power
Pinemarten Offline
Member
Registered: 08/23/03
Posts: 122
Loc: Edmonton, AB, Canada
Testing: &#8730
Edit: Hey it worked! Better than ^-1/2

[This message has been edited by Pinemarten (edited 08-23-2003).]

[This message has been edited by Pinemarten (edited 08-23-2003).]
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#128605 - 09/09/03 07:17 AM Re: 3 phase power
jlhmaint Offline
Member
Registered: 05/25/02
Posts: 208
Loc: Fredericktown, OH, U.S.A
ã
do you just know this stuff or do you have a list or something that you can pass on

[This message has been edited by jlhmaint (edited 09-09-2003).]
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