




#129159  08/30/04 11:14 PM
Phasor Resolution?.

Member
Registered: 07/05/02
Posts: 8553
Loc: SI,New Zealand

Hi Scott and the regulars here. I have a question that I hope that you guys can help me answer. I have done these sorts of calcs a million times before, but owing to lack of practice in the last few years, I've forgotten how on earth they're done. OK, here we go: A given 3 phase Starconnected installation, has the following Phase currents:  R Phase= 30A
 Y Phase= 25A
 B Phase= 40A
Having this information, how then is the current likely to be carried by the Neutral calculated?. Thanks in advance, Mike Trump.
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Let's face it, these days if you're not young, you're old  Red Green

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#129165  09/05/04 07:03 AM
Re: Phasor Resolution?.

Member
Registered: 09/17/02
Posts: 1508
Loc: Stockholm, Sweden

Tensors are used in some engineering calculations. I think the relationship between scalars, vectors and tensors is something like: Scalar: x This box weighs x ounces.  Vector: x, y I want this box x feet from that wall, y feet above the floor.  Tensor: a b c d I want to know how much stress ( tensiontensor, get it?) the hole for the box places on the wall. I don't remember how to calculate this, just that tensors were useful  Here is a proper description of tensors: http://www.physlink.com/Education/AskExperts/ae168.cfm You can even apply tensors to Ohms law: http://www.tf.unikiel.de/matwis/amat/semi_en/kap_2/basics/b2_1_3.html

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#129166  09/05/04 11:35 AM
Re: Phasor Resolution?.

Moderator
Registered: 04/10/02
Posts: 2561
Loc: WestSouthern InnerNortheast ...

Thank you, CH. ‘A tensor may be defined at a …collection of isolated points of space (or spacetime), or it may be defined over a continuum of points.’Now, maybe that’s sort of like explaining n thdimensional systems. The simplest shadow of a 2dimensional plane is a 1dimensional line. The simplest shadow of a 3dimension cube is a 2dimension plane. [The simplest shadow of a 1dimension line is a “zerodimension” point.] Outside of the human realm, the simplest shadow of a 4dimensional “object” is a 3dimensional form called a tesseract—which we view in 3 dimesions to be (roughly) a set of nested cubes. We cannot perceive a 4dimension object—only its 3dimension shadow. Will someday be useful for polychoroniodic tetrasesquiphase zeptojoule power analysis..} http://pw1.netcom.com/~hjsmith/WireFrame4/tesseract.html (drag cusrsor through image) http://mathworld.wolfram.com ..search for ‘Magic Tesseract’ (drag cursor through java image) http://en.wikipedia.org/wiki/Tesseract Rest in peace, Doctor Sagan... [This message has been edited by Bjarney (edited 09052004).]

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