Jordfejlstrøm

Jordfejlstrøm, also known as earth fault current, is an electrical current that flows through the earth when there is a fault in an electrical system. This type of current is typically the result of a live conductor coming into contact with the earth or a conductive object. The primary purpose of jordfejlstrøm is to activate protective devices, such as residual current devices (RCDs) or earth fault protection devices, which are designed to detect and interrupt the fault current to prevent electrical shock and fires.

The magnitude of jordfejlstrøm is influenced by several factors, including the impedance of the earth, the fault resistance, and the system voltage. In low-voltage systems, jordfejlstrøm is typically measured in amperes and is used to set the trip level of protective devices. In high-voltage systems, the current may be measured in kiloamperes.

Proper management of jordfejlstrøm is crucial for ensuring the safety and reliability of electrical systems. This includes regular inspection and maintenance of protective devices, as well as adherence to electrical safety standards and regulations. In some cases, additional measures may be taken to reduce the risk of earth faults, such as the use of insulated conductors or the implementation of earthing systems designed to minimize the flow of fault current.