Hi all.

questions about working with STEP 7 classic and TIA PORTAL STEP7

***

yes, I also know that different PLCs have different call times and block openings - but the question is about the general concept

***

There is a question about the performance and applicability of the code and designs on blocks below.

Question #1

What is more productive - transferring data to a block from a data block (such as FC) or processing this data inside FC from a global data block .

Example:

When calling a block, pass the structure from the data block to the block

Or process this structure directly by referring to the data block to which it is located

Question #2 (related to the question above)

When you open a data block (DB) inside the SCL code, does it remain open until another DB is called or until the block where it is called is closed?

Unreality

Hi all.

questions about working with STEP 7 classic and TIA PORTAL STEP7

***

yes, I also know that different PLCs have different call times and block openings - but the question is about the general concept

***

There is a question about the performance and applicability of the code and designs on blocks below.

Question #1

What is more productive - transferring data to a block from a data block (such as FC) or processing this data inside FC from a global data block .

Example:

When calling a block, pass the structure from the data block to the block

Or process this structure directly by referring to the data block to which it is located

Question #2 (related to the question above)

When you open a data block (DB) inside the SCL code, does it remain open until another DB is called or until the block where it is called is closed?

 You should read a few Siemens documents like Programming guideline and styleguide. Those will open a lot of information to you regarding 1200/1500 plc's.

Programming Guidelines and Programming Styleguide for SIMATIC S7-1200 and S7-1500

You can process tags from a DB, in multiple FC's and FB's at the same time.

Thanks for the documentation

However, the question is precisely what is actually more productive?

The that this can be created to 1200/1500 series and in the 300 series is a fact. But what is optimal? and is there a difference?

For example, when compiling the FC code - TIA said that "warning, global data blocks are used in the block ..." May be it is not optimal?

Unreality

Thanks for the documentation

However, the question is precisely what is actually more productive?

The that this can be created to 1200/1500 series and in the 300 series is a fact. But what is optimal? and is there a difference?

For example, when compiling the FC code - TIA said that "warning, global data blocks are used in the block ..." May be it is not optimal?

 It depends what you mean with optimal, it can be understood so many different ways. The siemens documents are the best practice. Also when you build the code according to the siemens documents, the code stays modular and you can re-use the blocks in different type of projects.

Okay, we figured out the first one a bit (although there is still a performance issue)

But is there an answer to the second question?

***

Question #2 (related to the question above)

When you open a data block (DB) inside the SCL code, does it remain open until another DB is called or until the block where it is called is closed?

Unreality

Okay, we figured out the first one a bit (although there is still a performance issue)

But is there an answer to the second question?

***

Question #2 (related to the question above)

When you open a data block (DB) inside the SCL code, does it remain open until another DB is called or until the block where it is called is closed?

 

 I already asnwered to question #2