ECN Forum Forums Technical Discussion Electrical Theory and Applications 3 phase power

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!

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.

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).]

√

ã ã ã ã

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




[This message has been edited by Bjarney (edited 07-02-2003).]

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).]

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.

I have no idea what happened to that line

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).]

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).]