Safety By Protection

Electric machinery, such as generators, transformers, auxiliary systems, bus bars, overhead lines and cable feeders, etc. have to be provided with protective features which will respond to internal and external faults and/or overloads or inadvertent false control operations to limit damages to a minimum by selective and co-ordinated isolation of the respective electrical plant portion thereby ensuring continuity of supply and safe operation for the remaining power system.

The properties of the electrical plant and the kind of applied equipment as well as the operating experience of the Power Authority and economic considerations for new constructed equipment will eventually determine the selection of the electrical protection system.

Also during modernising and refurbishment of existing plant flexible devices and systems capable of providing an optimal technical and economic solution have to be applied.

By use of versatile devices the spare part requirements can also be reduced to a minimum.

Besides the main tasks of a protective scheme, i.e. protective functions, modern protection systems will offer a series of additional functions such as extensive self-monitoring, fault- and event records, remote communication with control systems, etc. The self-monitoring feature provides a continuous availability check of the protective scheme and by analysis of the fault records an efficient and detailed clarification of the fault event sequence can be made.

Operation of the devices is facilitated via modern graphic User software which is providing a sense of "Look and Feel" and a clear optical display. False parameter settings are to a large extent prevented by the User program.