1794-aent

A customer of mine is experiencing some strange problems with discrete input status from Flex IO via Ethernet IP from 1756-ENBTs. The Flex is in MCCs and some input status bits quit for no apparent reason. The input LED is on, but the bit associated with it in the module tags is off. Three inputs have done this from one adapter so far and they quit at different times. Once they quit, they do not recover. Replacing the TB3 and the IA16 does not correct the problem. Haven't tried replacing the AENT yet. I went over the configuration and program to ensure it was correct and that logic was not writing over the bits affected. The Ethernet is a distinct network for the IO of this machine only. Has anyone experienced problems like this? I have used lots of flex over Ethernet and have never seen this.

I have seen this on flex i/o over RIO networks when a pin gets corroded or bent between the TB3 modules. In my cases, the bent pin was two modules to hte left of the one giving trouble.

Hmmm

Okie is right, I've seen a bent pin cause issues. I'm going to keep an eye on this thread. I just recently integrated a lot of AENT modules with flex I/O remote racks in our plant....they are a great solution so far, but they don't have much runtime under them yet. Spent a lot of time segregating the Ethernet network properly per AB's recommendations.

I'd be curious to know if anyone has had issues with AENT modules in general...

Greg

There were a number of 1794-AENT adapters manufactured in 2004 with an incorrect chip. We received a few on a project here and they exhibited the intermittent behaviour you describe.

See attached file.

Thanks Guys,

I'll forward this thread onto the customer.