What does XIC represent in ladder logic?

In ladder logic programming, XIC stands for "Examine If Closed." This instruction is used to evaluate a particular input condition to determine if it is true (closed) or false (open). When the program encounters an XIC instruction, it checks the status of the corresponding input; if the input is energized (or closed), the instruction allows the rung to pass power to the next device or rung in the ladder logic diagram.

This function is essential for controlling the flow of electrical signals within a control system, as it functions as a fundamental building block for decision-making in the logic. The ability to assess the state of an input is crucial for executing control logic, making this a foundational concept for anyone working with programmable logic controllers (PLCs).

The other options presented do not accurately describe the function of XIC in ladder logic. For instance, "XOR Input Condition" and "Exclusive Input Control" suggest operations that do not align with the primary function of XIC, while "Extended Input Coil" does not correspond to any standard terminology in the context of ladder logic. Understanding that XIC is synonymous with "Examine If Closed" allows one to effectively apply this knowledge in designing and troubleshooting ladder logic programs.