Siemens + PLC SIM and few questions

Hello,
I started doing some projects but soon found out that limited number of imputs outputs in template is too small.

As novice both for Factory I/O and PLC in genetal there are few thing i don’t understand and can’t find any answer.

“Make sure input addresses that will be used by Factory I/O are not assigned to any I/O module” - how do i know what input addresses are used by Factory I/0?

It is reapeatly said that you need to offset inputs if you have more of them in Factory I/O or Tia Portal. What confuses me is the OR bit, since it only worked for me when i changed start Adresses to 10 in both applications.

  1. Could somebody kindly explain in leyman terms what “MHJ-PLC-Lab-Function-S71200” block do?

  2. Don’t know if it’s related, but there is number in actuator/sensor tags that i can change before tag name. Like "5: Send left ". There is no such tag in various tutorial and i didn’t find any info what’s it’s for.

Hi @Map111,

“Make sure input addresses that will be used by Factory I/O are not assigned to any I/O module” - how do i know what input addresses are used by Factory I/0?

The input addresses used by Factory IO can be deduced from the I/O point offset and count in the driver configuration window.
plcsim-io-points
For example, ‘bool inputs’ is configured with offset = 5, and count = 14 which results in addresses between %I5.0 and %I6.5 being used by Factory IO.

You can also get that information directly by looking at the schematic in driver window:

It is reapeatly said that you need to offset inputs if you have more of them in Factory I/O or Tia Portal. What confuses me is the OR bit, since it only worked for me when i changed start Adresses to 10 in both applications.

Input addresses used by Factory IO should not overlap with addresses used by physical inputs.
Factory IO writes values directly to the PLC process image (I memory). When other input modules share the same addresses, the PLC’s CPU will, at the beginning of the cycle, copy the state of physical inputs to I memory, overwriting the values sent by Factory IO.
This will cause the inputs from Factory IO to seem intermittent, or not to show at all.
https://cache.industry.siemens.com/dl/files/129/109764129/att_974298/v1/s71200_system_manual_en-US_en-US.pdf#page=83

The issue is described in more detail here: Siemens: inputs not working


Could somebody kindly explain in leyman terms what “MHJ-PLC-Lab-Function-S71200” block do?

The function is responsible for allowing communication between Factory IO and the simulator.
It was provided to us by MHJ-Software, and I’m not sure how it works.


Don’t know if it’s related, but there is number in actuator/sensor tags that i can change before tag name. Like "5: Send left ". There is no such tag in various tutorial and i didn’t find any info what’s it’s for.

The number before the tag name is the tag address. It is mostly an implementation detail that doesn’t affect most users of Factory IO (it is mostly used with the SDK).
There is an option to hide the tag addresses in the VIEW menu:
show-tag-address

When using the built-in drivers, the only thing that matters is the association between tags and I/O points represented in the driver window.