One shot instructions are a combination of bit instructions used while performing logical operations. They are instructions that primarily work with the last state (PLC scan) of a particular digital signal. They are useful when you want to perform a function just once for a PLC scan. Different PLC manufacturers have different names for one shot Siemens calls it a positive and negative trigger, Mitsubishi names it a rising and falling pulse. The function, however, remains the same regardless of the name. In this tutorial, we will be looking at the different types of one-shot instructions available in Allen Bradley’s Studio 5000.
This is a companion discussion topic for the original entry at https://www.solisplc.com/tutorials/one-shot-instruction-ons