The ADD, also known as the Addition, is an instruction which will perform a mathematical addition of two integers or floats. Performing an addition has a lot of uses in PLC programming. In addition to the obvious, it can be creatively used to create advanced functions such as step counters, average calculations and so on. The instruction takes three operands: two which will be added and one into which the result will be stored as the instruction executes.
This is a companion discussion topic for the original entry at https://www.solisplc.com/tutorials/plc-programming-computational-mathematical-instructions-add-addition