1734-AENT Loss of Communications

[Drew Ethridge]

I have a small system with an L33ER controller communicating with three 1734-AENT modules. I used the GSV command to get the status of the ethernet modules.

Yesterday two, and possibly all three, AENTs stopped communicating. I can't say whether it was simultaneously or not. Cycling power resolved the problem.

The only thing that I could find that looked unusual was that the "Task Overlap Count" was quite high, around 3000 after several weeks of use. I had inadvertently left it at 5ms from when I was testing and had not increased it when the system was deployed.

Would these overlaps eventually cause the AENTs to drop offline?
Is there anything else I should be looking at to find the root cause?

Lastly, I understand that "16384" means good, but is there any documentation as to what other numbers mean? I was seeing 4096 and 12288, which like 16384, are simply multiples of 4096.

I said "several weeks" of running. But that was with only with one AENT. We just added the other two 7-10 days ago.

 

[jholm90]

Here are the details on the GSV for Entry Status:

Specifies the current state of the specified map entry. The lower 12 bits should be masked when performing a comparison operation. Only bits 12...15 are valid. Each value has a specific meaning:
• 16#0000. Standby. The controller is powering up.
• 16#1000. Faulted. Any of the Module object’s connections to the associated module fail. This value should not be used to determine if the module failed because the Module object leaves this state periodically when trying to reconnect to the module. Instead, test for Running state (16#4000). Check for FaultCode not equal to 0 to determine if a module is faulted. When Faulted, the FaultCode and FaultInfo attributes are valid until the fault condition is corrected.
• 16#2000. Validating. The Module object is verifying Module object integrity prior to establishing connections to the module.
• 16#3000. Connecting. The Module object is initiating connections to the module.
• 16#4000. Running. All connections to the module are established and data is transferring.
• 16#5000. Shutting down. The Module object is in the process of shutting down all connections to the module.
• 16#6000. Inhibited. The Module object is inhibited (the inhibit bit in the Mode attribute is set).
• 16#7000. Waiting. The parent object upon which this Module object depends is not running.
• 16#9000. Firmware Updating. Firmware supervisor is attempting to flash the module.
• 16#A000. Configuring. Controller is downloading configuration to the module

https://literature.rockwellautomation.com/idc/groups/literature/documents/rm/1756-rm003_-en-p.pdf#page215

As for the new AENTR dropping offline, I had issues last year with one out of the box that was communicating properly, then 1/2hr later stopped and required reboot. After moving the device to the same panel as the processor and disconnecting everything and direct wiring the the AENTR to the processor it dropped out as well. This was after flashing firmware and removing all slices etc. Warranty claim and replacement solved this issue for me.

 

[Drew Ethridge]

jholm90

Thanks for the detailed response. I had run across that manual in the past but had not had time to dig into it. I will make that time now.