Secondary selective system residual bus transfer - a modern application approach

A traditional secondary selective residual bus automatic transfer scheme is reviewed, and the basic logic necessary for automatic transfer operation is discussed. Although many transfer scheme documents are available, the authors believe the scheme complexity should challenge application engineers to better understand the "why's" rather than the "how to's" of the application. A modern programmable logic controller approach is proposed as a contemporary solution to a complex control application.

I. Introduction

A SECONDARY selective residual bus automatic transfer system with traditional discrete control and protection devices is discussed. The traditional discrete device system is also reviewed from a control, protection, and system design viewpoints. A modern programmable logic controller (PLC) transfer approach indicates the advantages of implementing a contemporary solution to a complex control application.