The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Neutral of major part of power transformers in electrical energy system with effectively earthed neutral is isolated. Isolated neutral is protected by valve-type arresters or lately by surge arresters. As a result travelling wave of lightning discharge to the line electromagnetic impulse is coming to transformer causing overvoltages in transformer neutral. If protective characteristics of surge arrester...