Ylijännitesuojaimen

Ylijännitesuojain is a Finnish term that translates to surge protector or surge suppressor in English. It is an electrical device designed to protect electronic equipment from voltage spikes or surges. These surges can be caused by various sources, including lightning strikes, power outages and restorations, and the switching on and off of high-power electrical equipment.

A ylijännitesuojain works by diverting excess voltage away from the connected devices. Most surge protectors contain metal oxide varistors (MOVs) or similar components that act as voltage-sensitive resistors. When the voltage is within the normal operating range, the MOVs have very high resistance and do not interfere with the power flow. However, if the voltage spikes above a certain threshold, the resistance of the MOVs drops dramatically, creating a low-impedance path to ground. This diverts the excess energy away from the connected equipment, protecting it from damage.

These devices are commonly used to protect sensitive electronics such as computers, televisions, home theater systems, and other appliances. They are available in various forms, from single-outlet adapters to multi-outlet power strips with integrated surge protection. The effectiveness of a ylijännitesuojain is often measured by its joule rating, which indicates how much energy it can absorb before failing. A higher joule rating generally signifies better protection. Regular surge protectors do not prevent power outages, but they safeguard against the damaging voltage fluctuations that can occur during such events.