What is "dead time" in process control?

Dead time in process control refers specifically to the delay that occurs between the application of a control input and the observable effect it produces in the system. This concept is crucial in understanding how processes respond to changes made by controllers. For example, when a control action is implemented, such as adjusting a valve or changing a setpoint, there is typically a lag before the output variable starts to change due to process dynamics. This delay can affect the stability and performance of control systems, and engineers must account for it to design effective control strategies.

In contrast to dead time, the other options focus on different aspects of operational processes. The time between production cycles pertains to scheduling and production management rather than control system dynamics. Maintenance checks relate to the upkeep of equipment, while periods of equipment inactivity concern downtime that can arise for various operational reasons. All of these do not accurately define the concept of dead time within the context of process control.