funksjonsjordleder

Funksjonsjordleder is a conductor used to establish a functional earth (FE) reference for electrical equipment and circuits. Unlike the protective earth (PE) conductor, whose primary purpose is to carry fault currents to prevent electric shock, a funksjonsjordleder is designed to provide a stable return path for signals, a reference for measurement equipment, shielding, and EMI management. It is not meant to carry fault currents during insulation faults and may be isolated from PE except at designated equipotential bonding points.

Applications include radio and telecommunications equipment, control systems, computer networks, medical devices, and any apparatus that requires a defined earth reference without relying on the safety earth to handle fault currents. In many installations, the funksjonsjordleder is connected to PE at a single point to maintain a common reference, while keeping it separate to avoid unsafe fault current in normal operation. The conductor may be connected to equipment cabinets, shielding enclosures, or specific terminals, and the configuration should follow applicable standards such as IEC 60364 and local regulations (e.g., NEK 400 in Norway).

Color coding for a separate funksjonsjordleder is not universally standardized and may differ by country; consult local codes. Designers must ensure that the FE does not compromise safety; if a fault occurs, the safety earth path must still be available. Regular testing and documentation of FE connections are recommended.