Överspänningsmotstånd

Överspänningsmotstånd, also known as overvoltage protection or transient voltage suppression, is a critical component in electrical systems designed to safeguard against the harmful effects of voltage surges or spikes. These surges can originate from various sources such as lightning strikes, switching events in power systems, or electrical faults.

The primary function of överspänningsmotstånd is to limit the voltage across electrical equipment to within safe operating limits. This is achieved through several mechanisms, including:

1. **Clamping**: Överspänningsmotstånd devices clamp the voltage to a predetermined level, preventing it from rising above a safe threshold.

2. **Absorption**: Some devices absorb the excess energy from the surge, dissipating it safely.

3. **Redirection**: Others redirect the surge current to a safe path, away from sensitive components.

Common types of överspänningsmotstånd include:

1. **Metal Oxide Varistors (MOVs)**: These are non-linear resistors that provide a low impedance path for surge currents while maintaining high impedance under normal operating conditions.

2. **Gas Discharge Tubes (GDTs)**: These devices use a gas mixture to conduct surge currents, providing a high impedance under normal conditions.

3. **Transient Voltage Suppression Diodes (TVSDs)**: These are semiconductor devices that conduct in the reverse direction during voltage surges, protecting against both positive and negative transients.

Proper selection and placement of överspänningsmotstånd are crucial for effective protection. Factors such as surge magnitude, duration, and system impedance must be considered to ensure that the protection device can effectively clamp or absorb the surge without failing or degrading over time.

In summary, överspänningsmotstånd plays a vital role in maintaining the reliability and safety of electrical systems by providing a means to mitigate the damaging effects of voltage surges.