Hello, everyone

I am developing a FB to control a pallet transfer system in Tia Portal V18.Due to the large amount of processing it performs and also for better monitoring, I decided to divide it into five subroutines using multiple instances within the main FB.Once the block was developed, its correct operation was verified through simulations.

The problem arose when I needed to use the main block for the second time. The execution of the subinstances of the first and second main FBs began to exhibit abnormal behavior, such as: intermittent contacts, uncontrolled segment startups, and bugs throughout the environment (It should be noted that this problem only occurred when the main block was instantiated for the second time).

The diagnostics performed were:

• Check that each general FB has its own individual instance
• Each general FB accesses global DB variables in separate sections

However, I haven't been able to find a concrete solution to the problem. The only way I've gotten it to work is by generating separate instances for each block executed within a FC

Given this problem, is there some limitation to using multiple instances of custom FBs, or perhaps it's due to poor handling or variable declarations?

I've attached excerpts from the block in question.

Thanks for your response. The other DBs you mentioned belong to the instances within the FC I mentioned.To isolate the problem, I created a test project.

Here's a cleaner image of the program.

Thank you for your response.In this case, there are no global DB variables present within the main FB.In fact, the project itself, being a test project, does not have global DBs.

I've attached excerpts to show the full contents of the main FB.