Simplified electrical test procedures for components of isolated LPS

Recently IEC TC 81 decided to set up PWI 62561-8 in order to extend the IEC 62561 family (Lightning Protection Components) by a new part 8 (Requirements for components for isolated LPS). The paper works out the basic electric characteristics of components of isolated LPS which require standardization. It describes and discusses test procedures that cover the dielectric strength and the capability to withstand lightning current of components of isolated LPS in order to link the possibilities of (new) components for isolated LPS with the requirements of the IEC 62305 series. With the definition of a new wave shape 1/200μs which takes the negative first lightning stroke into account , some new approaches and requirements are considered in the test procedures. The paper briefly revisits the basics of the calculation of separation distances according to the current standards - impulse-voltage-time characteristic and the constant-area-criterion. Based on these facts a simplified high voltage impulse test is derived which works with the standardized voltage impulse 1.2/50 μs. This is a high voltage impulse test to cover the needs for testing the dielectric strength of the non-metallic or composite component design of an insulating fastener and the dielectric strength of the insulating layer of cables used as insulated down conductors. The same test also covers the creepage discharge behavior of the potential grading at insulated down conductors. A high current impulse test is discussed in order to classify insulated down conductors due to their lightning current withstand capability. Finally these tests procedures had been applied to insulating fasteners and cables used as insulated down conductors. The preliminary results of these tests are presented and discussed by means of their applicability for standardized testing. The aim of this contribution is to help to provide an acceptable, simple and physically correct basis for suitable electrical test procedures that support the development of the new 62561-8 standard.