Overtilspænding

Overtilspænding, in electrical engineering, refers to a voltage that exceeds the normal operating level of a system or component. This can occur due to a variety of reasons, including lightning strikes, switching surges, and faults in the power grid. While temporary overvoltages are common and systems are generally designed to withstand them, prolonged or severe overtilspænding can cause damage to sensitive electronic equipment, insulation breakdown, and potential power outages.

The impact of overtilspænding depends on its magnitude, duration, and the susceptibility of the affected equipment. Lightning-induced overvoltages are typically very high in magnitude but short in duration. Switching surges, which occur when electrical circuits are opened or closed, can also cause significant voltage rises. Faults within the power system, such as short circuits, can lead to overtilspænding on other parts of the network.

To protect against overtilspænding, various protective devices are employed. Surge protective devices (SPDs), also known as surge arresters, are commonly used to divert excess voltage away from sensitive equipment. These devices typically contain non-linear components that conduct current only when the voltage exceeds a certain threshold. Proper grounding and insulation are also crucial in mitigating the effects of overtilspænding. In high-voltage applications, sophisticated insulation coordination techniques are employed to ensure that insulation can withstand expected overvoltage levels.