Spänningsdämpare

Spänningsdämpare, known in English as surge protectors or surge suppressors, are devices designed to protect electrical and electronic equipment from voltage spikes or surges. These surges are sudden, brief increases in voltage that can be significantly higher than the normal operating voltage. Such events can damage sensitive components within electronic devices, leading to malfunction or complete failure.

The most common cause of voltage surges is lightning strikes, either direct or indirect. Even if a lightning strike doesn't hit a building directly, it can induce surges in power lines and communication cables that travel into the building. Other causes include the switching of heavy electrical loads within a building, such as air conditioners or industrial machinery, and faults in the electrical grid.

Spänningsdämpare work by diverting the excess voltage away from the connected equipment and safely channeling it to the ground. They typically contain components like Metal Oxide Varistors (MOVs) or Transient Voltage Suppressors (TVS diodes). When the voltage exceeds a certain threshold, these components become conductive, creating a low-impedance path for the surge current to flow to ground, bypassing the protected equipment.

These devices are available in various forms, from simple power strips with built-in protection to sophisticated whole-house surge protection systems installed at the main electrical panel. The effectiveness of a spänningsdämpare 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. It is important to note that spänningsdämpare do not prevent all types of electrical problems, such as brownouts (low voltage) or complete power outages.