Lisämaadoitus

Lisämaadoitus, meaning supplementary or additional grounding in Finnish, refers to an extra protective measure in electrical installations. It is distinct from the main protective earthing system but serves a similar purpose: to enhance safety by providing an additional path for fault currents. This can involve connecting exposed conductive parts of equipment, which are not part of the main earthing circuit but could become live in case of a fault, to the main earthing terminal or another earth electrode.

The primary goal of lisämaadoitus is to reduce the risk of electric shock. If an insulation fault occurs within an appliance, causing its metal casing to become energized, lisämaadoitus ensures that this fault current can flow safely to the earth. This rapid dissipation of current typically triggers protective devices like circuit breakers or fuses, disconnecting the power supply and preventing a dangerous voltage from persisting on the accessible parts.

Lisämaadoitus is often implemented in specific situations where an increased level of safety is deemed necessary. This can include locations with a higher risk of shock, such as bathrooms, kitchens, or outdoor environments, or for certain types of electrical equipment. The requirements and implementation details for lisämaadoitus are typically specified in national electrical installation standards and regulations. It is a crucial concept in ensuring the integrity and safety of electrical systems beyond the basic protective earthing.