Micrologix 1400 Faulting

Hey all, looking for a little insight on a problem I have had come up 2 days in a row now...

We have a micrologix 1400 running a fairly simple program running a bottle filler. Twice now, I have been called out to troubleshoot something not working on the filler, and it winds up being a major fault on the 1400. Project dumped. I have not invested a whole lot of time trying to find the root cause of the problem yet, but I was wondering if any of you might know of a common problem with these, or if it might probably be due to a gremlin in my control panel.

Another detail to the story: Yesterday in addition to clearing the fault and re-downloading the project, I also found that I had a bad output. An output that only fires a small relay. I installed this PLC to replace another 1400 a couple of years ago, to fix the same problem. The old 1400 was starting to burn up outputs as well.

Are these super sensitive to noise or something? Everything is properly grounded around here and it is a 24vdc model, so it the feed goes through a power supply (SOLA SDN 5-24-100P). I wouldn't think that over/under voltage would be a concern right off the bat.

Any and all comments are appreciated!

From the manual...

0002 UNEXPECTED RESET • The controller was unexpectedly
reset due to a noisy environment
or internal hardware failure.
• The default program is loaded.
Non-User •Refer to proper grounding guidelines and
using surge suppressors in your controller’s
User Manual.
•Verify battery is connected.
•Contact your local Rockwell Automation
representative if the error persists

Click to expand...

Jason,

I have frequently used ML1400's in bottle fillers (and in other equipment). I have not seen this problem in bottle fillers, but in other equipment I have seen where a short circuit, or suspected high current on an output will cause this kind of fault in the PLC. The instance I remember best was with an output firing a fairly large hydraulic solenoid (relay output - 120VAC coil). I 'fixed' it with an interposing relay - i.e. an output fires a relay, which in turn fires the hydraulic solenoid. This was not a high speed machine, so this fix worked good.