Motor Bus Transfer Applications Issues and Considerations

This paper presents the results of an investigation of motor bus transfer (MBT) applications issues and considerations by a Working Group of the IEEE PSRC Rotating Machinery Protection Subcommittee. The specific task was to investigate protection and control issues as well as phenomena impacting the effectiveness of safely transferring buses primarily consisting of motor loads from one power source to another source. Areas addressed are technical literature, manufacturers information, members experience with plant applications, history, application approaches, computer modeling, field measurements, and industry guidance. This knowledge will help enlighten users to benefit their applications with regard to motor bus transfer protection and control. There are many challenges associated with proper application of motor bus transfer systems. These will be addressed in this paper.