DHRIO w/1771 IO Erroneous Adaptor Timeout Error

I have a 1756-L81e v32 using a DHRIO v7.001 in RIO scanner Driving (7) 1771 ASB Modules @ 115k baud. The Racks RPI are set at 48msecs. This system has been running for about 2.5 years. I have verified that there are 2 resistors 150 ohm on each end of the Network. From End to End the system is laid out like this. Resistor/Rack 26--> DHRIO Scanner--> Rack 10-->Rack 11-->Rack 13-->Rack 14-- Rack15-->Rack 16/Resistor.

About 5 months ago we showed a Rack Fault on Rack 13 in the PLC. This was determined by a GSV reading Rack 13 Fault code not equal to 0. However when we went to Rack 13 in the field it was back green lite and Running. The only time I've been there when the GSV reported a fault the 1771-ASB was blinking green. This meaning it wasn't being actively scanned then went right back to solid green without any help from me. This leads me to believe that the DHRIO is loosing connection with Rack 13 for some reason. Around 2 months ago we did a full rip and replace of Rack 13. Everything but the IO cards themselves. We changed the Power Supply, Chassis and Adaptor Card and didn't have a problem again until a few days ago.

I'm getting Adaptor Timeouts and Retries constantly but haven't had another "Fault" since Sunday.

I have checked the Cabling and Terminations several times but all seems well. Don't really know what the next logical step is. ???

The Picture below is only about 6 hours of runtime.

Bump

It honestly wouldn't surprise me for one of the replacement parts to have failed too. It looks like a slightly different problem, which would be consistent with that. None of that stuff is new, even if you manage to get something with the factory seal intact. You got 45 timeouts in 6 hours, which is less than 10 minutes between them.



Is the DH+ network a straight daisy-chain connected to 3-pin Phoenix connectors? If not, it should be. If so, and if you have the time, you might try disabling and disconnecting one rack at a time to see if the timeout counts change. Not sure how exactly to disable it so the DHRIO isn't looking for it, but there "ought to" be a way.