Do capacitor banks need surge arresters?

Many capacitor banks are operated without surge arresters. However, there are a variety of reasons to instal arresters: To prevent capacitor failures at a breaker restrike or failure. To limit the risk of repeated breaker restrikes. To prolong the service life of the capacitors by limiting high overvoltages.

How does capacitor size affect surge arrester energy stress?

The following results are obtained: A single-stage capacitor bank (Fig.1) is used to vary the three-phase bank size in order to evaluate the effect on the surge arrester energy stress. Depending on the arrester arrangement, a linear increase of the energy dissipated in the arrester is obtained.

Do surge arresters reduce MV & HV capacitor overvoltage?

Installation of arresters also minimizes probability of restrike, especially of multiple restrikes. This edited past contribution to INMR by Tim Rastall and Kerim Ozer of Enspec Power in the United Kingdom discussed application of surge arresters for mitigation of overvoltages on MV & HV capacitors based on single restrike.

Can a surge arrester protect a capacitor?

Generally speaking, capacitor protection by surge arresters has been a difficult task before Z n O arresters became available. The high discharge currents and possible energies associated with an arrester operation at a capacitor bank heavily stressed the spark gaps in a S i C gapped arrester.

What are the protection settings for a capacitor bank?

Moreover, the protection settings for the capacitor bank unfold systematically, elucidating the process of selecting the current transformer ratio, calculating rated and maximum overload currents, and determining the percentage impedance for fault MVA calculations.

What is a capacitor bank?

The primary objective of this capacitor bank is to enhance the power factor of a factory. Local regulatory standards dictate that the power factor for bulk supply connections must be maintained at 0.9 or higher.