Pojavi na talilnem elementu varovalke v talilni fazi izklopa

slovenian

2004

volume 38, issue 1/2

Inštitut za kovinske materiale in tehnologije
(Obvezni izvod spletne publikacije)

Test samples of melting fuses rated for a current of 63 A were subjected to tests with a breaking current of 100 A, where the melting of the fuse element is the principal process of current interruption. Particular sites of the fuse element strip, notches, are coated with an alloy with a low melting point and in this way they enable the break of the overcurrent by melting and dissolving the base Cu strip. The investigation of the fuse elements was performed after the break tests and involved optical microscopy, metallography, SEM and EDX microanalysis of the chemical composition. Results were analyzed using binary diagrams of Cd-Sn, Cu-Sn and Cd-Cu. The effects of phenomena which occasionally prolong the melting process were investigated in order to reduce excessive heating of the fuse link during the break. As a prolonged type of melting phase could be thermally harmful to the adjacent plastic parts of insulation, measures to avoid it are important for the design of the fuse element and its manufacturing technology.

16.09.2009