This Technical Specification deals with the protection of PV installations against overvoltages. It deals with the protection of the PV installation against surge overvoltages induced by direct and indirect lightning strikes. If such a PV installation is connected to an AC-supply system this document is applicable as a complement of HD 60364 4 443, HD 60364 5 534 and HD 60364 7 712 and also CLC/TS 61643 12. Surge protective devices (SPD) installed on the AC side shall comply with EN 61643 11. NOTE 1 Due to the very specific electrical setup of PV installations on the DC side, only surge protective devices especially dedicated to PV installations shall be used to protect the DC side of such installations. NOTE 2 Taking into account the sensitivity and of the setting up of the photovoltaic modules, a detailed attention must be paid to the protection of the structure itself (building) against direct effects of the lightning; this subject is covered by EN 62305 series.