Every power plant has an added control system. These systems may have small or large amounts of automatic functions. These functions might include a control of the reactor flow or reactivity balance as a result of temperature monitoring. For example, it might be required to maintain a constant or near constant outlet temperature. Thus this additional control function is also a feedback that needs consideration during any safety evaluation.

Such feedbacks are entirely dependent on the design of both the plant and its control system. However, control system criteria for the design will ensure that such feedbacks contribute to the stability of the system rather than detract from it. Indeed they have the ability to make the system stable despite any adverse inherent feedback loops there might be.

The next section will make further reference to control and protective system feedbacks in the reactor system closed loops.