Dryhops
Member
I made a post about this issue a few months back but it has been persistent and a solution is elusive. I could really use some insight from those more experienced.
I'm having connection issues with a Controllogix 1756-L72, with only a 1756-EN2TR in it's chassis. The primary symptom is that the HMI (Ignition based) will update values for about 5 seconds, then the tags go stale and the controls freeze up. After a few more seconds, the tags begin to update again. This behavior cycles constantly and has occurred since the initial install.
The connection path looks like this:
1756-EN2TR >>> 9300-ENA (NAT device) >>> ~230 Ft heavily shielded Cat6 >>> Unmanaged N-Tron 1080X swtich >>> Server
What I have tried:
1. Checked the port diagnostics, definitely showing errors. If I swap to the other port on the EN2TR, the errors begin to accumulate there.
2. Research into FCS errors suggests an auto negotiation failure or EM interference, or even bad cabling. I rebuilt the cable ends. I ran two entirely new cables (Not in the wire rack to rule out EM).
3. I bypassed the unmanaged switch and connected directly to a different controllogix with a EN2TR. I explicitly set both sides of the connection to 100 full duplex. I tried all possible manual combinations. I tried another unmanaged switch too. (Other devices are successfully using this switch)
4. I bypassed the 9300-ENA NAT device by addressing the EN2TR on our SCADA IP range.
5. Thinking perhaps it was signal degradation, I tried putting a switch in the middle of the cable.
6. Spent a few hours with ignition support. Everything is properly configured.
7. Checked continuity of the chassis ground.
8. I ran a wireshark capture. There is definitely some level of packet loss. Here is an example, I can post the entire capture if that would be helpful:
All of this seems to suggest a faulty EN2TR to me. I do not have a spare to try swapping it out right now. They are pretty expensive, so it would be hard to justify a large expenditure unless I can exactly pinpoint how this is failing. So how can I audit the operation of the EN2TR to better understand what is causing these errors to occur? I'm currently checking out the AOI profile to make sure I didn't mess that up during the installation. Are there any other mistakes that a novice like myself might have made in the setup?
Any help or suggestions would be greatly appreciated.
I'm having connection issues with a Controllogix 1756-L72, with only a 1756-EN2TR in it's chassis. The primary symptom is that the HMI (Ignition based) will update values for about 5 seconds, then the tags go stale and the controls freeze up. After a few more seconds, the tags begin to update again. This behavior cycles constantly and has occurred since the initial install.
The connection path looks like this:
1756-EN2TR >>> 9300-ENA (NAT device) >>> ~230 Ft heavily shielded Cat6 >>> Unmanaged N-Tron 1080X swtich >>> Server
What I have tried:
1. Checked the port diagnostics, definitely showing errors. If I swap to the other port on the EN2TR, the errors begin to accumulate there.
2. Research into FCS errors suggests an auto negotiation failure or EM interference, or even bad cabling. I rebuilt the cable ends. I ran two entirely new cables (Not in the wire rack to rule out EM).
3. I bypassed the unmanaged switch and connected directly to a different controllogix with a EN2TR. I explicitly set both sides of the connection to 100 full duplex. I tried all possible manual combinations. I tried another unmanaged switch too. (Other devices are successfully using this switch)
4. I bypassed the 9300-ENA NAT device by addressing the EN2TR on our SCADA IP range.
5. Thinking perhaps it was signal degradation, I tried putting a switch in the middle of the cable.
6. Spent a few hours with ignition support. Everything is properly configured.
7. Checked continuity of the chassis ground.
8. I ran a wireshark capture. There is definitely some level of packet loss. Here is an example, I can post the entire capture if that would be helpful:
All of this seems to suggest a faulty EN2TR to me. I do not have a spare to try swapping it out right now. They are pretty expensive, so it would be hard to justify a large expenditure unless I can exactly pinpoint how this is failing. So how can I audit the operation of the EN2TR to better understand what is causing these errors to occur? I'm currently checking out the AOI profile to make sure I didn't mess that up during the installation. Are there any other mistakes that a novice like myself might have made in the setup?
Any help or suggestions would be greatly appreciated.
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