In a lead-lag system, what condition favors the activation of the lag unit?

In a lead-lag system, the activation of the lag unit is favored when the lead unit is overworked. This scenario occurs when the lead unit is unable to handle the current workload due to factors like high flow rates or increased demand on its capabilities. In such cases, the lag unit is activated to support the lead unit and ensure that the system continues to maintain efficiency and stability.

By having the lag unit activated during times of excessive demand on the lead unit, the system can distribute the workload more effectively, preventing potential bottlenecks and optimizing performance. This mechanism is crucial in wastewater treatment or industrial processes where maintaining flow and processing capacity is vital for operational success. The lag unit thus serves as a backup, ready to be utilized when the primary unit (the lead unit) reaches its operational limits.