Allen Bradley Math Errors

[Gil47]

I don't use the ML1400 at all but can't you see from the processor properties where the fault originated?

Keith

Yes you can,
you look in the status file S2 and check the Errors Tab, but it must be
checked before a power recycle as you may lose some of the info

 

[Ron Beaufort]

can't you see from the processor properties where the fault originated?

not IF (that's a big IF) it's a math overflow fault ... (remember I'm still GUESSING here - until we get a look at the program file) ...

the trick is that having a math overflow does NOT cause a fault ... specifically, the processor keeps right on chugging along after the overflow - BUT - it does write a ONE status to the S:5/0 bit in order to "remember" that a math overflow has occurred ...

then ...

when the processor finally gets to the end of its scan (usually the last rung in Ladder File #2) - IF the S:5/0 bit still contains a status of one, THAT"S WHEN the fault occurs ... so ... if this is what is causing the fault, the processor's "where did the fault occur" entry will always show the last rung in Ladder File #2 - instead of the location where the math overflow actually occurred ...

some extra detail is available here:

http://www.plctalk.net/qanda/showthread.php?p=14393&postcount=6