Functional equipotential bonding is the compensation between conductive parts by means of an electrical connection in order to achieve equal potential, it does not serve a protective purpose. A functional equipotential bonding conductor is required, for example, if a new building is erected with a concrete foundation that has an increased earth transition resistance, e.g. in the case of a white tank or perimeter insulation. In this case, a ring earthing rod is laid, which is connected to a functional equipotential bonding conductor within the building foundations for potential control. Both are connected to the equipotential bonding rail.
Source: bauwion
