In message <de87437fe365cb458c265ea3d73b6f1dd99...@xbc-mail1.xantrex.com>, dated Fri, 3 Feb 2006, Ralph McDiarmid <ralph.mcdiar...@xantrex.com> writes >Perhaps "resultant current" or "net RMS current" would have been better >than "vector sum". A vector sum implies to me, drawing the vectors and >adding them graphically, or adding their real & imag rectangular >components.
Vector summation takes phase into account, or, what is the same thing, real and imaginary components. > >If I recall correctly, the RMS (effective) value is also the >square-root of the algebraic sum of the squares of the magnitudes of >the harmonic terms. Yes, and eliminates phase information. That's why we have to put it back in to calculate: power = VIcos[phi] > >I understand that these RCCB devices do this sum, presumably by a >resultant flux in a magnetic circuit. Now, how would a magnetic circuit calculate RMS values? (I wish it could.) -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk 2006 is YMMVI- Your mileage may vary immoderately. John Woodgate - This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas emcp...@ptcnh.net Mike Cantwell mcantw...@ieee.org For policy questions, send mail to: Jim Bacher: j.bac...@ieee.org David Heald: emc-p...@daveheald.com All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
