jordfejlstrømsafbryder

A jordfejlstrømsafbryder, often abbreviated as RCD (Residual Current Device) or GFCI (Ground Fault Circuit Interrupter) in English, is a safety device used in electrical installations. Its primary function is to protect individuals from electric shock and to prevent fires caused by electrical faults. It works by continuously monitoring the electrical current flowing through a circuit.

In a properly functioning circuit, the current flowing out on the live wire should be equal to the current returning on the neutral wire. If there is an imbalance between these currents, it indicates that some current is leaking out of the circuit, likely through a person or a faulty appliance into the ground. This leakage current is known as a residual current.

When the jordfejlstrømsafbryder detects a residual current above a certain threshold, typically 30 milliamperes (mA) for personal protection, it rapidly interrupts the electrical supply. This interruption happens much faster than a conventional circuit breaker can react to overcurrent, significantly reducing the risk of serious injury from electric shock. It does not protect against overcurrents or short circuits; for that, a separate circuit breaker is still necessary.

Jordfejlstrømsafbrydere are essential safety components in modern electrical systems, particularly in areas where the risk of electric shock is higher, such as bathrooms, kitchens, and outdoor areas. They are mandated by electrical safety regulations in many countries to enhance the safety of electrical installations and users.