Grounding solar panels

How to ground solar panels? Photovoltaic systems are typically installed on roof of the houses or on large open spaces, where is bigger possibility of lightning strike. Consequences of lightning strike are destroyed photovoltaic modules also other electrical equipment in the house because of connection between the photovoltaic system and electrical installations in the home.
To ensure safe and uninterrupted operation of PV system throughout its life cycle it is necessary to be provided complete protection from lightning and induced high voltages. Protection should  be provided on DC side also on AC side from the DC/AC converter

Lightning protection460x300

Photovoltaic system with built in surge arresters between field bus connector of photovoltaic modules and DC/AC converter.

If the distance between photovoltaic module and inverter is less than 25m then is enough installation of only one lightning arrester , otherwise it must be installed two. Distance between the PV modules and lightning protection conductor on the roof should be greater than 0.5 m.If that is not possible to be achieved, then the photovoltaic modules should be connected with lightning conductor which is connected to ground.
Goal is that lightning current doesn’t flow through the metal frame of photovoltaic modules.If photovoltaic modules is not connected to the lightning conductor or the house doesn’t has lightning protection installation than photovoltaic modules should be connected directly with the ground. For the grounding should be used deeply buried in the soil steel or copper rod or plates. Grounding provides a rapid discharge in surrounding soil. DC/AC converter is protected with lightning arrester on the DC side also on AC side. Surge arresters on the DC side should be selected according to the open circuit voltage value of the photovoltaic source.

4 Responses

  1. Prashant says

    Can we connect only one live wire with surge arrester or it is mandatory to connect both the wires woth grounding?
    What about three phase system?

    • admin says

      Regardless of whether the wire is + or – should be linked to surge arresters.
      For 3 phase system, all 3 phases and neutral wire should be connected to separate surge arresters.

  2. nova says

    Is a metal racking system a required pqrt of PV instalation?

    • admin says

      No is not required metal rack. It is used because of better mechanical characteristics. But you must have some sort of protection from lightning.