Which instruction is used to examine if a condition is closed?

The instruction used to examine if a condition is closed is the XIC (Examine If Closed) instruction. This instruction is essential in ladder logic programming as it allows the PLC (Programmable Logic Controller) to check the status of an input or a condition. When the XIC instruction encounters a closed condition, it evaluates to true, which enables the associated output or next actions in the control sequence.

In practical applications, for example, if a switch or sensor is in a closed state (which typically represents an active or true condition), the XIC instruction will allow current to flow through the rung, potentially activating outputs or other functionalities downstream in the ladder logic. Thus, it plays a crucial role in ensuring that the desired actions take place only when specific conditions are met, facilitating accurate control of systems and processes.

Understanding the use of the XIC instruction is fundamental in the context of programmable logic controllers, as it directly relates to the ability to make decisions based on input states.