Residential solar system bonding and grounding methods for lightning protection

Photovoltaic (PV) panels are typically roof-top mounted and the DC/AC inverters are either collocated or installed inside the building. The PV system is grounded to grounding-electrode according to NFPA70-NEC690.41-64. The roof-mounted PV panels are susceptible to direct lightning strikes. In order to minimize personal and property damages, lightning surge currents must be drained to the earth through low resistive paths. This article discusses multiple electrode grounding for minimizing lightning damages. The effectiveness of multipoint grounding electrodes and their installation distances for different soil resistivity are discussed.