On an S7-1200 or an S7-1500 there are four places a function block can keep state that is not in its instance DB, and every one of them makes a second FB instance of FB_Valve share memory with the first. The report is always one of three: valve 2 opens when valve 1 is commanded, … Read more
Tag naming, rung comments, UDT and AOI descriptions, pass-through and L5X exports that keep a Studio 5000 or TIA Portal project readable years later.
If you are using Control Logix plc, we will make a flip-flop example with AOI. I will show you how to easily make a flip-flop block with add-on instructions. Normally, you can use one Timer On and one timer-off instruction for the flip-flop circuit. But creating a new one for each flip-flop circuit would be … Read more
Importing an Add-On Instruction Definition Perform this procedure when you want to use the definition for an Add-On Instruction that was exported from another Logix Designer application project. Once the project has the definition, you can use the instruction in your programs. Right-click on the Add-On Instruction folder and select Import Add-On Instruction from the … Read more
How to Create Add-On Instructions in Logix Designer One of the most powerful newer features of the RSLogix 5000 program is the ability to create Add-On Instructions, It is one of the features that makes the algorithm easy and enjoyable for plc programmers. How to create and use the Add-On instruction Now we will go … Read more
Safety Add-On Instructions Like standard Add-On Instructions, safety Add-On Instructions let you encapsulate commonly-used safety logic into a single instruction, making it modular and easier to reuse. In addition to the instruction signature used for high-integrity Add-On Instructions, safety Add-On Instructions feature a safety instruction signature ID for use in safety-related functions. Refer to the … Read more
Add-On Instructions Add-On Instructions are user-defined instructions. When you define an Add-On Instruction in a project it behaves similarly to a built-in instruction. You can define these instructions or they can be provided to you by someone else. An Add-On Instruction enables you to encapsulate your most commonly used logic as sets of instructions. These … Read more