The Application of Computers in 600MWe CANDU Shutdown Systems

Abstract

The use of microcomputers or Programmable Digital Comparators (PDCs) in domestic CANDU 600 MWe plants is the first major application of digital logic in CANDU shutdown systems. These units have been installed to provide reliable and flexible conditioning logic for six process trip parameters in each of the two shutdown systems which these CANDU plants employ.

The PDCs systems use commercial off-the-shelf hardware which has been modified and qualified to meet the environmental requirements for a nuclear power plant application. Since the PDCs have been designed to provide accurate, reliable and fault tolerant conditioning logic, they are expected to contribute significantly to improved operating margins and shutdown system availability.