Timer (TON) not Timing - RS 500 / ML 1400

[theColonel26]

Ok guys I have a strange one. I just added a timer to to ML 1400 program, and it is not accumulating anything. But the OTE after the XIC TT instruction is true.......

I have done a cross reference of the Timer and it is not used any where else. further my HMI does not access any of my Timers directly so it can't be that writing in. Also the routine is called and is executing everything else just not this TON.


Side Note: the big branch around everything at the start of the rung was just to eliminate those XIOs as being the cause of the issue.



WTF?

I have a script that copies this set of logic 18 times, in to offset registers, it is doing it on every single instance of this logic. I am perplexed.


See video.


https://drive.google.com/file/d/12L5VdkQouMhH7XyyrnrR4Ez9oOvH7XWe/view?usp=sharing

 

[Jim3846]

I don't see a RES bit, so that is not being held on in the cross referencing.
Are you calling this routine from the main? That gets me too when I am in hurry.
Your TON is on rungs 8 and 17. Delete one on rung 17 and retry.

 

[77nomad]

Is there an MCR rung or are you not calling the routine with a JSR?

 

[MikeyN]

Your TON is on rungs 8 and 17. Delete one on rung 17 and retry.

This is most likely the problem. When rung 8 evaluates, T40:5.EN is enabled and technically timing, so the output will energize. When it gets to rung 17, T40:5.EN is no longer enabled, so the timer stops timing. By the time the whole scan is finished the timer is not enabled, so nothing accumulates, and the TT bit is turned off. Do as Jim suggests, delete the one on rung 17. Or better yet, if you are in a position to do some testing and waste a little time, manually toggle the timer on rung 17 at the same time and see what happens. Try with the timer off at rung 8 and on at rung 17 and see what happens to the outputs.

 

[geniusintraining]

Maybe.... N20:2/0 is your issue, you are toggling the bit but its unlatched in the next rung down, so I dont think its really true

 

[theColonel26]

I don't see a RES bit, so that is not being held on in the cross referencing.
Are you calling this routine from the main? That gets me too when I am in hurry.
Your TON is on rungs 8 and 17. Delete one on rung 17 and retry.

Yaaaaaaah, I do not how I missed that

 

[theColonel26]

Maybe.... N20:2/0 is your issue, you are toggling the bit but its unlatched in the next rung down, so I dont think its really true

The TON on Rung 17 was the issue.

Rung 9 is only executed if T40:5/TT goes to false. I have an OSF, not an OSR.