qwazee

Dear Ragul Gandhi. It is regrettable to hear about your continued struggles.

You are making a big ask. We have no insight of how the machine looks and what it does. Making changes blindly is not good.

The program you provide is not documented. Not even any field notes from your side were added to the code to identify what the functionality of each code block. To do this job proper will take effort which cannot be expected as a free service from a volunteer.

Ask specific question and the forum volunteers might have specific answers. 

As an unimportant side note - Your Step7 V17 is out of date. We are at Update 6 now. I do not recommend you change your software now as there is no benefit for you now.

 okay i understand. I try to modify other Blocks please help me for some STL blocks its very hard to understand. and help me how to do the scaling for S5 FB250 and FB251 in S71200 PLC in Tia portal. 

Segment1:

Segment 2:

Please help me to understand this function to convert LAD.

0_Einstein

In portal F1-Help, when you search for DECL, some questions for you:

• What did you find the instruction does
• What parameter does it require
• What changes in the PLC after running the instruction
• After running several of them in rapid succession, what do you *think* happens

After all, that's the very first segment and once you know what the first one does, you should be able to extend that to the rest, and then knowing where the data comes from, you should be able to arrive at a conclusion what that segment needs to do.

From there, you should be able to replace it with something equivalent in LAD - using just the words you assigned to the segment comment / note.

As for segment 2, I recommend trying to convert it to SCL in the original PLC project first using Classic Step 7 or TIA Portal.  If you can do that, you are well on your way to solving the problem.

Of course, you can try dropping in a few lines of STL (at a time) into an S7-1500 project's FB or FC and try letting Portal convert it for you.  Eventually, you will start to get the hang of it.

And, by now you should know what L and T STL instructions do, and possibly what the A instruction might look like in LAD.  I bet there are online guides showing LAD equivalents to a great many of the STL instructions.  I bet if you use those online guides, you could translate 80% (possibly more) to LAD all on your own without a lot of knowledge.  Perhaps that's just me, but I have done that, and I still know very little about STL - mostly just the above suggestions -- and how to read TIA Portal's F1-Help as well as the STL instruction pane's description for each STL instruction.

 Yes i am following this way to solve other FB blocks to convert LAD but some instruction i cant solve it because when i am running with the machine i am facing the issue . now i have the problem with only the above STL program and the Scaling and Unscaling block for S5 PLC FB250 and FB251 . please help to solve for this because now the machine is not running .

qwazee

 

0_Einstein

In portal F1-Help, when you search for DECL, some questions for you:

• What did you find the instruction does
• What parameter does it require
• What changes in the PLC after running the instruction
• After running several of them in rapid succession, what do you *think* happens

After all, that's the very first segment and once you know what the first one does, you should be able to extend that to the rest, and then knowing where the data comes from, you should be able to arrive at a conclusion what that segment needs to do.

From there, you should be able to replace it with something equivalent in LAD - using just the words you assigned to the segment comment / note.

As for segment 2, I recommend trying to convert it to SCL in the original PLC project first using Classic Step 7 or TIA Portal.  If you can do that, you are well on your way to solving the problem.

Of course, you can try dropping in a few lines of STL (at a time) into an S7-1500 project's FB or FC and try letting Portal convert it for you.  Eventually, you will start to get the hang of it.

And, by now you should know what L and T STL instructions do, and possibly what the A instruction might look like in LAD.  I bet there are online guides showing LAD equivalents to a great many of the STL instructions.  I bet if you use those online guides, you could translate 80% (possibly more) to LAD all on your own without a lot of knowledge.  Perhaps that's just me, but I have done that, and I still know very little about STL - mostly just the above suggestions -- and how to read TIA Portal's F1-Help as well as the STL instruction pane's description for each STL instruction.

@0_Einstein: Please read the content of this topic. The TIA Portal help does not help for analysing the S5 program. You may find the manual I have linked to earlier as somewhat of an education, if ever you wish to learn STL.. or specifically the STL of the S5.

By the way.. DECL -> declaration.

 Segment 1 is okay they mentioned the name and assign Input and Output . But segment 2 there is a calculation . can you please help me to solve i need to compare if my conversion is correct or not .