FFL True/False condition.

[KirillIvanov]

Hello everyone.


Quick Newbie FFL question.



As far as I understand from YouTube etc. FFL should be energized by True condition from the left. Like:
True |------------------| FFL works


I've put a bit from the left to control the loads but it appears that it works only when this bit is not energized. Please see EN conditions on Screenshots.
Screenshot 1 - Shceme.
Screenshot 2- the only condition I've got FFL to work.


Every time I put a new number at N7:70 it's loaded to FFL no matter if B3:1/1 energized or not. I assumed that B3:1/1 can be removed if it doesn't change anything but it doesn't work with empty condition.



Screenshot 3 0 > 0 which should be False gives a green on EN.


Is this normal or my Emulator doing miracles?
Thank you.


It's 1100 Series B running on RSLogix Emulate 500

 

[OkiePC]

I would only expect to see the EN bit set when the rung in conditions are true. Are you sure that your control word is not used anywhere else?

 

[KirillIvanov]

I would only expect to see the EN bit set when the rung in conditions are true. Are you sure that your control word is not used anywhere else?

Yes, absolutely. B3:1/1 used only once. That's the first thing I did. Checked with "Find all"

 

[blftech]

Where is the logic that controls bit B3:1/1.
Also, what is the purpose of the temporary end instruction?

 

[OkiePC]

Yes, absolutely. B3:1/1 used only once. That's the first thing I did. Checked with "Find all"

What about R6:0 ? Do a "Find All" on that address.

 

[KirillIvanov]

Where is the logic that controls bit B3:1/1.

Still nothing controls it. I'm just doing "Toggle Bit" manually.

Also, what is the purpose of the temporary end instruction?

At some point I didn't want it to execute the second part if the checked bits are empty.

I'm playing with it few hours and changed the logic many times so perhaps right now it doesn't have any sense.
Well... I removed it and now everything works as expected!


Thank you.