While Ladder Logic uses the element position on a rung to create logic expressions, Function Block logic expressions are handled by dedicated Function Block elements. In the next sections, we will explore some of the logical Function Block elements that are available and see how they are used.
AND logic in Function Block
Within a Function Block routine, you can evaluate an AND logical expression using the BAND function block. This block will evaluate an AND logical expression using all the input references passed into it and provide the solution to its output reference pin. The following diagram shows the same simple AND logical expression in Function Block:
When the StartPump and StartPumpManualOverride input references are both true, the RunPump output reference will energize. Note that the input reference values to the right on the input reference pins indicate the current value...
