Lightning Arrester Design as a Security System for Photovoltaic Systems in Pematang Johar Village

The design of lightning arresters on photovoltaic systems aims to secure buildings from lightning strike disturbances, because the electronic devices contained in the system are relatively expensive and vulnerable to external disturbances. Considering that the thunderstorm days in the Medan City area are quite high, namely 224 days/year, and the topology of the area in the rice fields makes photovoltaic very vulnerable to lightning strikes. Therefore, to avoid the impact of lightning strikes, the photovoltaic system needs to be equipped with an external lightning protection system. The method used is to analyze several parameters such as conductor crosssectional area, grounding grid resistance value, building area, touch voltage and step voltage. Then it will be simulated using Etap Power Station software to determine the resistance of the lightning arrester system that has been designed. From the analysis results, it is obtained that the ground resistance is 1 $\Omega$, the ground resistance is 4.7 $\Omega$ and has an efficiency value of 0.72% which is classified as protection level III. Then the maximum current that the lightning arrester can withstand is 6 kA and the current discharge time is 0.3 $\mu$s. As for avoiding the induction effect that will have an impact on humans due to lightning strikes, it is recommended that a safe distance ranges from 30 m from the reference point because it has a touch voltage value and a step voltage that meets the tolerable voltage.