Modicon M340 bits dropping out? high to low

[ChrisMartin]

Hey guys, I'm having something very strange happening, I have a certain number of MW's dropping out. This is causing shut down and alarming. They aren't all in sequence ie. MW1201.2, MW1203.3, MW1203.4, MW1213.2 etc.
These MW's are coming off of physical inputs but I have proven these inputs are not coming in by creating a debounce timer and creating an alarm before the debounce timer, the alarm did not come in but the latched MW's did drop out. Strange really, any thoughts out there as to why this would be happening internally?

 

[ChrisMartin]

Here is an image that might help understand it's only the latch bit that appears to drop out??

 

[ChrisMartin]

Hey guys, I'm having something very strange happening, I have a certain number of MW's dropping out. This is causing shut down and alarming. They aren't all in sequence ie. MW1201.2, MW1203.3, MW1203.4, MW1213.2 etc.
These MW's are coming off of physical inputs but I have proven these inputs are not coming in by creating a debounce timer and creating a WARNING coming off of the input LSHH_24002, the LSHH_24002_WARN did not come in but the LSHH_24002_LATCH did drop out. Strange really, any thoughts out there as to why this would be happening internally?

 

[goghie]

We need more details in order to help you. Send us program and we may help you.

 

[shrirampendse]

Is it not related to using TON without wiring EN and ENO ?
Pls check.

 

[ChrisMartin]

actually that TON did not exist prior to the problem starting, take out the TON and the LSHH_24002_WARN and that's what we had before and the LSHH_24002_LATCH was dropping out I built the debounce timer to troubleshoot if this was coming from the input. So really the TON is new and still having same issue.

 

[ChrisMartin]

OK, so my previous action of putting in a Warning did not seem to function very well as I did more research and found that the input was dropping out, and that my warning wasn't coming in. Very strange but that is another problem. So it is looking more like it is coming from the field, have disconnected a few devices and not had an issue yet so think that one of the devices might be the culprit. Not sure why my warning never came in, might have something to do with timing, not sure how long it takes for Vijeo Designer runtime to notice alarm? anyone?