Binary code in Ladder Logic Programming
In this second part of the Binary Code in Ladder Logic, we are going to explain another examples of Binary Codes.
The OR function examines multiple PLC inputs and has one resulting output. If we translate an OR function into a Ladder Diagram, we can express it symbolically in the form of two PLC inputs A and B using normally open contacts (NO) and a PLC output Y using relay coil.
The OR function examines if any of the PLC inputs are TRUE, then the corresponding result is also TRUE. However, all the PLC inputs must be FALSE in order for the corresponding result is also be FALSE.
In a PLC, binary events are expressed symbolically using ladder logic in the form of a normally open contact (NO) and normally closed contact (NC). The normally open contact (NO) is TRUE when the event is active and FALSE when the event is NOT active. While the Normally Closed Contact (NC) is FALSE when the event is active and TRUE when the event is NOT active.