1794-aent module error

Good day all,

i have a 1794-aent that went faulty today.

The module status light is flashing red and the network light is solid red.
If i go into rslogix 5000 v19, i can see the yellow warning on the io module in the tree.
I right click to see port configuration and try reset module but i get an error to say code16#0005 connection request error bad class. or i get cip error in communication request. Module mismatch.

I have check the ip address and even reset module to factory settings and assigned ip again using bootp then disabled bootp. but still the error.

I plugged laptop directly to the module and did bootp then rslinx could see it and the status of the module said ok.

The minute i plug the module back into the networkm then the module status flashes red again.

I also get incorrect module cip object does not exist.

I can ping the module and i can see it in rslinx but its got the red x over it. and in rslogix 5000 it just keeps saying faulted.

Any thoughts or info would be greatly appreciated.

Check to see if you have any IP clashes on the network. Something else might be sharing the AENT's IP address.

All of your descriptions very strongly suggest that there is a duplicate IP address on the network.

The solid red Network Status LED is the 1794-AENT's way of telling you that there's duplicate IP address.

When you try to connect with RSLinx and get a bunch of messages about " bad class" and "no CIP object", that is a strong indication that you are connecting to something else, not the 1794-AENT.

Some Cisco switches also send out a packet that causes some Rockwell products to incorrectly detect a duplicate IP, but the rest of your symptoms point to a true duplicate IP.

The simplest way to test that is to PING the IP address of the 1794-AENT while it is disconnected from the network.

Once you've PINGed the device, use "ARP -A" to learn its MAC ID, and look that up to figure out what vendor the device is. Also see if the device has a built-in web page by putting its address into a Web browser.

Its strange because it is not a new installation. Machine been off for 2 days maintenance. Nothing new was added.

If i right click the module in rslogix 5000 then the name of module says rslinx. It does not show 1794-aent.

Not counting what you are seeing in software, I have have had numerous failures over the years that exhibited the same behavior with the status lights. Yes a duplicate IP can cause it but most of mine were failed AENT or IO modules. First test should be to unplug your AENT from the rest of the group and see if it still faults. If it doesn’t you have a bad IO module.

Another thing to check is if the fault comes within a few minutes of power up. If it does then you might have one of a batch of bad AENT out there. They were made in either 2014 or 2015 and have a knowledgbase article about it. I can personally attest that Rockwell is still honoring replacements on these as of about two months ago when I had one go bad.

whats strange is, i power up and the module status light is flashing red straight away, and the network status is solid red.

If i unplug from the machines network, then the module status is green and network flashing green.

I tried also to plug direct into module and i reset ip and i can see it no errors within linx, but if i plug back into network then it goes red again

I've had that happen using Stratix switches to assign addresses by port. They just assign random addresses from the pool if multiple devices power on at one time. The Automation Direct SE2 Series switches work properly for DHCP per port.

just to update this issue i had, i replaced the aent adaptor today and i had the same issue, the module status kept flashing red. I then went to see the module diagnostics and the name of the device was wrong, instead of 1794-aent, it was showing rslinx.
I then unplugged the module and went to pint the ip address and got a reply even though it was unplugged. So traced a few devices and found that the technician had plugged a pc into the switch and the ip address was the same as the "faulty" module.

unplugged the pc and all was good.

I suppose the lesson here is trust that the rslinx, rslogix network is not happy when the status lights are showing what they show.

thanks all for the help