T & D Protection & Control MiCOM P740 Numerical Differential Busbar Protection An innovative solution to increase stabilty , security and reliability of the supply. The P741 (Central Unit) and the P742 and P743 (Peripheral Units) form the MiCOM P740 system. This can be adapted to provide the right solution for a particular busbar configuration. The MiCOM P740 numerical busbar protection scheme satisfies a large number of requirements including: Numerical technology , • Speed, reliability, security, • Analysis of coherency between peripheral units, • Adaptable to either a traditional centralised cubicle scheme and/or benefits of peripheral units distributed in other equipment, • Fibre Optic inter-connections, • High sensitivity for internal faults, high stability for all external faults. The P740 can be used in a wide variety of substations and at all voltage levels including applications such as: • MV and HV distribution substations, • HV and EHV transmission substations, • Railway network substations for 2-phase feeders, • Solid or impedance-earthed substations, • Pump-storage hydroelectric generating substations, GIS substations with single phase and three phase compartments. Busbar protection • Busbar protection with multiple tripping criteria (87BB) • Overcurrent & earth fault protection (51, 51N) • Blind spot / dead zone protection (50) Additional protectio n functions • CT supervision • Trip circuit supervision • Circuit breaker failure logic (50BF) in peripheral units • Programmable scheme logic Measurement and recording facilities • Measurement & display ofall analogue & calculated quantities Post fault analysis • Sequence of events log • Fault records • Disturbance recorder Plant supervision • Substation plant maintenance information • Continuous diagnostics & monitoring of protection scheme Configuration • Choice of language settings
