How does a high voltage surge arrester work?

How does a high voltage surge arrester work?

A surge arrester works by diverting the extra voltage into the earth wire, rather than flowing through the electronic devices, while at the same time allowing the normal voltage to continue along its path.

What is an operating duty cycle test on a surge arrester?

Duty cycle testing of an arrester is performed by subjecting an arrester to an AC rms voltage equal to its rating for 24 minutes. During which the arrester must be able to withstand lightning surges at 1-minute intervals. For station class arresters, the magnitude of this surge is 10kA (10,000 Amperes).

What is surge arrester in electrical?

A surge arrester is a protective device for limiting voltage on equipment by discharging or bypassing surge current. It diverts the lightning, limits the voltage and protects the equipment installed in parallel.

What happens when a surge arrester fails?

Surge arrester failure can result in short circuits in houses. In most of the situations, a fault occurs because of dielectric breakdown once the internal structure of the system damages. So the arrester cannot resist the applied voltage like lightning, normal system voltage, switching surge overvoltage.

What is the difference between surge arrester and lightning arrestor?

Surge Arrester: is a device used to protect the electrical installations and equipment from electrical surges and transient voltage caused by electrical faults, switching, short circuits, sparks and lightning etc. Lightning arresters are installed outside to ground the harmful effects of lightning spikes.

What is rated voltage of surge arrester?

It is necessary to use an 18 kV arrester with an MCOV of 15.3 kV. Finally, for a resistance-grounded 13.8 kV system, the choice will be between arresters rated 12 kV, 15 kV and 18 kV, depending on the time needed to relay ground faults off the system.

What is discharge class of surge arrester?

N MV HV Surge Arrester Line Discharge Class 3 AC Systems 72kV Indoor & Outdoor. N surge arresters are used for the short-circuit protection of medium voltage and high voltage electrical equipment and cables against overvoltages caused by lightning, atmospheric discharges and switching conditions up to 72kV.

What is LCM testing?

The LCM can monitor the condition of high voltage Surge Arresters in service. The LCM measures the resistive component of the leakage current of the Arresters. Increased resistive current indicates a higher risk of breakdown of the Arresters.

What is Thrc test?

The method with indirect determination of the resistive leakage current component by means of third harmonic analysis with compensation for voltage harmonics (THRC) is one of the best available for on-site, in-service information and also diagnostic efficiency.