Safety of Photovoltaic Modules – an Overview of the Significant Changes Resulting from Maintenance of IEC 61730 Series

Abstract

Since release of Edition 1 of IEC 61730 series the photovoltaic industry has experienced rapid growth and undergone a large number of changes. As a result, during the past two years Working Group 2 (WG2) of the technical committee for Solar Photovoltaic Energy Systems (TC82) of the International Electrotechnical Commission (IEC) invested a considerable effort in updating the governing PV module safety standards to respond to PV industry needs as well as reflect technological changes and advances. In particular, with the revision of IEC 61730 a need to reflect the current understanding of low voltage DC (up to 1,500V d.c.) components and materials used in the construction of PV modules arouse. This includes permitting new materials and new designs while at the same time complying with international horizontal standards that need to be met in order to comply with governing national electric codes. Part 1 of IEC 61730 addresses the minimum requirements for module design while Part 2 deals with the required tests protocols and test sequences. New tests have been added to Part 2 of Edition 2 as the material requirements necessitate the confirmation of their properties during PV module operation. This paper explains the most crucial changes to Edition 1 of IEC 61730 series and shows that most PV modules on the market today already fulfill the requirements of the second edition. In this context it is important to understand the concepts of component approvals, insulation coordination, protection against electric shock, overvoltage category, protection class, material group and pollution degree as well as the resulting voltage limitation conjunction to minimum clearances (cl) and creepage distances (cr) and distance through insulation (dti) for cemented joints.