overstrøm

Overstrøm is the Danish term for overcurrent, the condition where electrical current exceeds the rating of a conductor, device, or circuit. Excessive current can cause overheating, insulation damage, arcing, and increased fire risk. Protection systems are used to detect and interrupt overstrøm to prevent damage and danger.

Causes of overstrøm include overload (continuous drawing of more current than a circuit is designed to carry), short circuits (faults that create a very low impedance path and large fault currents), and inrush currents (temporary surges when equipment starts, such as motors or capacitors). Transient switching events can also momentarily push current above normal levels.

Protection and design approaches aim to limit damage from overstrøm. Protective devices such as fuses and circuit breakers automatically interrupt current when thresholds are exceeded. Coordination and selectivity ensure that the device closest to the fault trips first, isolating only the affected section. Conductors and equipment are sized with margin for normal operation and anticipated inrush, and protection settings account for startup surges and ambient conditions.

Measurement and standards: Overstrøm is monitored with current meters and protective relays. The breaking capacity of protective devices must exceed expected fault currents. Standards from IEC and related bodies specify current ratings, fault levels, and testing procedures to ensure safe operation of electrical installations. Regular inspection and proper wiring, grounding, and insulation are important parts of preventing damage from overstrøm.