Secure data communication for line differential relays

By application of numerical differential protection devices over digital communication links it is possible to transfer, apart from the protection relevant data, additional binary information and measured values. Communication convertors adapt the telegrams of the devices to the communication medium. Apart from classical pilot wire links and optical fibres it is also possible to use modern communication networks for the transfer of data. With the application of WDM technology the few optical fibre cores between the stations can be used more efficiently. The protection equipment provides all the measuring and monitoring functions to ensure a data connection with very high security and dependability. This ensures a cost optimised and efficient solution for the transfer of protection related and additional data.