Changing what to seconds or minutes?

OB 40 is a hardware interrupt and will execute when the event it is attached to occurs, edge trigger maybe? And will execute only once and just long enough to go through the code you showed which, of the top of my head, will take considerable less than one millisecond. So when you are monitoring the code you are unlikely to see accurate depiction od the execution and it is best to read the results in a tag or add test tags to figure out if the interrupt and your code is executing.

Hello

Sorry for my late feedback, I left PLC for a while to focus on other part of my project and now I'm back.

By chaning to seconds I meant what's on the attachet screenshot (actually on both of them). I must chose a time unit from a sub-category of "curr time" while in on the screenshot from the thread below it looks like it wasn't necessary.

I have exacly reproduced the program from this thread https://support.industry.siemens.com/tf/ww/en/posts/why-this-doesn-t-work-s7-1200/138765/?page=0&pageSize=10 

and it will not work... I should be able to read the CONV value, not true? The whole network 2 stays innactive.

What am I missing?

I'm adding second attachement.

EDIT: Problem solved. There is no need to select second/minute etc... I didn't know/try to select "none" before and this was my problem. A pitty I didn't find that info anywhere.

Could anyone explain me please why it doesn't work when making a selection other than "none"??