Virtahäiriöiden

Virtahäiriöiden, better known as electrical disturbances, refer to irregularities in the flow of electric current that can affect the performance, safety, or reliability of electrical systems and devices. These disturbances include transient spikes, surges, harmonic distortion, voltage dips, and electromagnetic interference. Transient spikes are brief, high‑amplitude events often caused by lightning strikes, switching of large inductive loads, or cable faults. Surges, larger in magnitude and duration, may originate from grid anomalies or induction of stray current. Harmonic distortion, produced by non‑linear loads such as variable‑frequency drives, leads to over‑frequency energization of capacitors and overheating. Voltage dips or sags occur when supply voltage temporarily falls below the nominal value, risking equipment shutdown. Electromagnetic interference can radiate or conduct signals that disrupt the operation of nearby radio‑frequency devices.

The impacts of virtahäiriöiden span from reduced equipment lifespan and increased maintenance costs to safety hazards like arc flashes or data corruption. Preventive measures include installing surge protection devices, line conditioning systems, proper grounding, and isolation transformers. Regulatory bodies such as IEC and IEEE publish standards (e.g., IEC 61000 series) that define acceptable limits for each disturbance type. Effective mitigation relies on fault detection, real‑time monitoring, and periodic testing to ensure compliance with safety and performance standards.