Changes Proposed for the IEC 60093 Standard Concerning Measurements of the Volume and Surface Resistivities of Electrical Insulating Materials

摘要

The IEC 60093 Standard, prepared by the International Electrotechnical Commission in 1980, sets up methods of measurements, determination and calculation of volume and surface resistivities of solid dielectrics. The document contains some editorial mistakes as well as content-related inaccuracies that require revisions. Besides corrections of obvious editorial mistakes it is suggested to introduce some content-related improvements. The most important remarks given in the paper are associated with the following problems: 1) shunting of the current meter by the resistance between guarding and guarded electrodes; 2) significant influence of the electrodes made of conducting rubber on volume resistivity measurement results; 3) errors associated with application of simplified expressions for resistivitiy calculations (volume resistivity for tubular samples, surface resistivity for samples with circular electrodes); 4) increase of the effective surface of the measuring electrode (margin width determination and consideration). Finally, proposals of alterations of particular clauses of the standard, supplemented with appropriate justifications, were given in the paper.