What is a common method for programming PLC logic for timing tasks?

Employing timers and counters is indeed a common method for programming PLC (Programmable Logic Controller) logic for timing tasks. Timers can be set to operate for specific durations, allowing for actions to be executed after a predetermined time interval has elapsed. This is particularly useful in automation processes where timing is crucial—for instance, for controlling the duration of an operation, initiating a sequence of events, or managing delays.

Counters serve a similar purpose by tracking the number of occurrences of an event (like the number of inputs detected) and are also instrumental in controlling sequential processes. By integrating timers and counters into PLC programming, engineers can create logic that effectively manages timing and counting operations, which are essential functions in many industrial automation applications.

In contrast, relying solely on discrete inputs or conditional statements does not provide the necessary functionality for accurately implementing timing tasks. Discrete inputs, which typically deal with binary signals (on/off), lack the time-based control required for more complex timing actions. Conditional statements can help in decision-making but are not standalone solutions for managing time-dependent tasks without the support of timers and counters. Manual switches are also too simplistic and lack the automation and precision that a PLC with timers and counters can offer.