Printed circuit tracks, due to reduced values of their geometrical parameters (“track width - W” and “copper foil thickness - t”), do not allow the flow of any value currents. By this reason the designers and the users of PCB electronic modules have to take into account, between many other problems more or less important, also the current capacity of interconnection tracks.

The evolution of electronics in the last decades has simplified pretty much the things and it has reduced the difficulties involved by the aspects which will be treated in this module. The main reason is represented by the drastic breakage in voltages and currents from the electronic apparatus. If in the 60’ to know formulas and graphics about the maximum allowed currents through tracks represented compulsoriness for every engineer and electronics technician, nowadays at most 5% from the specialists know these things (and these ones forced by their implication in the domain of electronic technology or by the designing and fabrication of high power products).

Reword, the common electronics specialist, amateur or professional, is far away to be able to estimate the current limit in the case of a printed track, not few being the cases when electronic modules or products designed correctly on the paper were catalogued as rebuttals or low quality products only for the reason that a single track was interrupted (“was burning”, in the hobbyists language) because of the passing of a too large current through it, fact that has created small or large disturbances designed product.