FSM with timer interlocking

karl-johan Stjärna 6 years ago in IQANdesign updated 6 years ago 4


Is there anyone who could have a solution with example for below issue?

I would like a "machine tool" release digital output to be activated when "driver in seat" and "Tool release" button is engaged. But only if the driver in seat is engaged first so the tool does not fall off uncontrolled when turning around the chair if the "tool release" button is stuck or engaged by mistake.

I have tried with FSM but does not find a good solution, i believe there must be a timer involved to check if the tool release is engaged the first few seconds.

Image 1173


I would create a function group and place "Tool release", "OK to release tool", and "Machine Tool" inside it. Have "Driver in seat" outside of that previously created function group and use it to enable the function group. 

New Function group:

Thank you for quick reply, I have tested this way also.

However the issue is the same, if the "tool release" is accidently activated before the "driver in seat" the machine tool will fall of simultaneously as the chair is turned around.

I need a protection that blocks "OK to release tool"  until "tool release" has been reset to FALSE with "driver in seat" in TRUE.


Sorry, I read it too fast. I'm attaching a stripped file using a FSM to do what I think you want. If it's not, I think I'm out of ideas.

FSM tool release sequence.idsx


Thank you very much Chris!, this works just fine!!