Application of multi-function, micro-processor based protective relays in cement plants

The evolution in protective relays that started with simple discrete elements to replace electromechanical relays with static relays has resulted in the application of the modern multifunction, microprocessor based (/spl mu/PB) protective relays. The /spl mu/PB relays consist of elaborate schemes that include equipment protection, control, metering and communication to the plant control system. Further evolvement is envisaged. This paper reviews the present application of such relays in cement plants as related to high voltage and medium voltage equipment.