A Control System for Selectively Inhibiting Protection System Functions in a Research Pressurized Water Reactor

A scaled-down research pressurized water reactor (PWR) which is equipped with redundant emergency core cooling (ECC) systems with typical automatic actuation is running a series of simulated primary pipe rupture experiments. This facility requires that: a) only selected ECC pumps be actuated during experiments, while the other pumps are prevented from responding; b) the pumps which are selected can be pre-set to provide less than normal flow, and/or be delayed beyond their normal actuation time, and c) normal, full ECC flow from all pumps be automatically re-activated during experiments if necessary. A control system for meeting these requirements is described.