Hello everybody, I would like to know if the way I am following in modelling the reactive impedence is fine. I am talking about a "pair" (is it the right word in english ?) on a robot manipolar which does welding resistance. My goal is to evaluete which transformer's size will garantee the current that I need. It involve the calculation of the impedence that the transformer sees and in particular the impedence of the circuit. I have calculated the pair's area and the equivalent roud area which has R_eq=(S/3.14)^0.5. After that I have H and B then the flux. The result is mu*R_eq*3.14*log[2*R_eq/(4*R_eq*d-d^2)^.5)]. where d is the diameter of the pair's finger. Anybody has had similar result ? Since it is feed for 20-30 cycles (e.g. cycle= 20ms 50Hz) and after stops for some seconds, which frequency should I use if I want to calculate the reactance ? Any advice will be appreciate. Sincerely, Massimo Milizia.

-- Massimo Milizia (m.milizia@teoresi.it), February 28, 2000