Program control instructions alter the program flow of a PLC from what?

Program control instructions in a PLC (Programmable Logic Controller) are designed to modify the typical or expected behavior of the program, allowing for dynamic changes based on specific conditions or inputs. These instructions enable the PLC to execute distinct paths or decide whether to skip certain operations based on the current status of the system.

The concept of altering the "Normal Sequence" is crucial here because program control instructions are intended precisely for this purpose—changing how and when certain parts of a program are executed. This can include branching to different routines, looping through sections of code, or even jumping to different parts of the program based on the logic defined within those control instructions.

As a result, the emphasis on "Normal Sequence" highlights how these instructions facilitate a departure from a linear or standard routine. The control capabilities allow for more complex and responsive programming to react according to the real-time needs of the automated processes being managed by the PLC.