PZH R3 HSAF3* S (Hermi Surge Arrester Filter) is a two-stage surge arrester. It features a high-frequency filter integrated between the two stages. The PZH R3 HSAF3* S contains an improved thermal fuse, which ensures timely disconnection of the PZH R3 HSAF3* S from the power grid during overheating and thus prevents damage to the PZH R3 HSAF3* S. Activation of the thermal fuse is signalled by an integral indicator light (each phase is signalled separately) with the option to utilize its switching contact for remote fault signalling (S). The PZH R3 HSAF3* S is a type T3 two-port surge arrester and has been tested according to standards IEC 61643-11:2011 and CISPR 17:2011. According to standard IEC 62305:2010, it is installed in the boundary between zones LPZ 2 - LPZ 3, where it limits induced overvoltage and residual overvoltage in power lines. PZH HSAF* S is mounted on the main board of a switchboard using four bolts. Manufacturer’s recommendation: PZH R3 HSAF3* S is to be installed as close as possible to the protected device (max. 5 m). A T1 lightning arrester and T2 surge arrester from HERMI must be installed in front of PZH HSAF3*S.