PZH ZS-1 275 DS RS and PZH ZS-1 275 DS DI are surge arresters Type 2+3 (TYPE 3 protects the device only to 5m lead) according to IEC EN 61643-11 and IEC EN 62305 designed for LED lighting protection for installations largely e.g. in tunnels, properties and premises, street lights etc. Efficiently protect both the input supply voltage and the data communication lines for the remote control of lighting fixture (protocol RS485 eventually DALI (DI) ). Both types are equipped with the internal disconnecting signal contacts (DS), which are activated when the inbuilt varistor overheats above 136°C. The way to connect to a given application is by the pull-wire terminals.