The system contains self-monitoring procedures to activate backup sequences in the case of an emergency. There are four identical workstations in the Chooz B control room. Reactor operators at each workstation choose an operating display format and select an item using a trackball. The item then appears on a touch-sensitive screen so that the operator can select a command by checking the appropriate item. The item is confirmed by pressing a validation key.
Command history is displayed on-screen, as is an updated graphic presentation.
The Arabelle's steam flow arrangement reduces the number of turbine blades, and cost, by minimizing the stages requiring more than one row of blading. In addition, the control room is equipped with a wall-mounted mimic diagram that provides an overview of the unit's status. This eliminates the multiple alarms and indicator lights that were activated simultaneously in the past. A wall-mounted auxiliary control panel serves as backup if the central information system fails. Increasing Steam Supply Framatome engineers were given the task of increasing the steam power of the N4 reactors approximately 12 percent over the preceding generation of 1,300-megawatt reactors, while minimizing design changes.