The advent of composite insulators began first in the U.S. and soon after in Germany and France. User acceptance was slow at the start and these products went through the ‘teething’ problems common to most innovations. Moreover, their initial pricing made them too costly for widespread application.

Application of extruded XLPE cables in underground transmission systems has increased to the point that they now account for the vast majority of all new installations. This near total shift from oil and paper insulation has made it necessary to look for improved methodologies for type testing as well as commissioning testing of transmission class cables.

Application of RTV silicone coatings to porcelain and glass insulators in order to increase their pollution performance has been available for decades. Yet not everyone in the industry still appreciates how this coating technology operates and what factors will determine performance and effective service life.

Malaysia’s power system operates in a region of intense lightning activity that adversely impacts performance of certain lines, such as 132 kV Kuala Krai to Gua Musang line located in the northeast and the 500 kV Ayer Tawar to Bukit Tarek line which runs along the western coast of the Malay peninsula.

Since inception, IEC standards 60815-1 to -3 have helped guide engineers charged with specifying insulation for overhead lines and substations operating in polluted service environments. Recently, efforts have been underway to revise this standard to make it easier to implement and a Working Group within CIGRE is being set up with this specific goal.

Two types of fault currents can appear on power systems: ground and phase-to-phase. The more important when it comes to surge arresters is the first, which is basically the current that flows through the circuit when there is a short to ground.