What control approach is demonstrated when a limit switch starts the next event only after the previous event completes?

• A. Parallel control
• B. Sequential control
• C. Predictive control
• D. Reactive control

Answer: (B)

This is about sequential control—the system enforces an order where the next operation starts only after the current one has finished. The limit switch acts as a gate that signals completion and then allows the following step to begin, preventing overlap and ensuring proper timing. Parallel control would start multiple steps at once, which isn’t what's happening here. Predictive control uses a model to forecast future behavior and adjust ahead of time, not just wait for a current task to finish. Reactive control responds to changes as they occur, without a fixed stepwise sequence. So the described behavior aligns with sequential control.