40mpg
Member
Hello All,
I wonder if some of you can give me some insight in this problem that I have. Here are the symptoms
1. 1756-DNB/A DeviceNet Comm Module is in the same chassis as the ControlLogix PLC
2. RsNetWorx on first scan detects only nodes 0, 1,3,4, and 5. Node 2 indicates an identity mismatch, help file suggest to delete the node from the network graph and re-browse. Same issue
3. I power down the PLC chassis and removed the terminal block from the DeviceNet comm module, then reinsert. Just plain ol unplug and plug.
4. Power up the chassis, fire up RSNetWorx and went online, now the network sees node 0, 1,2 and 3 only
5. Repeat step 3 and 4
6. Now network only sees node 1 and 3
On the LED scroll on the DeviceNet Comm Module I see code 78, 5, and 4. Before the power cycle, I only see code 77, means mismatch data type according to the help manual. 77 went away after the power cycle.
This led me to believe that maybe the DeviceNet Comm Module is going bad. As Node 0 is the PLC that is on the same chassis as the comm module, if RSnetWorx sees the PLC intermittently then maybe the module is going bad?
Anyone encounter a similar issue with DeviceNet Comm Module? Any steps you have taken to further troubleshoot this issue?
I wonder if some of you can give me some insight in this problem that I have. Here are the symptoms
1. 1756-DNB/A DeviceNet Comm Module is in the same chassis as the ControlLogix PLC
2. RsNetWorx on first scan detects only nodes 0, 1,3,4, and 5. Node 2 indicates an identity mismatch, help file suggest to delete the node from the network graph and re-browse. Same issue
3. I power down the PLC chassis and removed the terminal block from the DeviceNet comm module, then reinsert. Just plain ol unplug and plug.
4. Power up the chassis, fire up RSNetWorx and went online, now the network sees node 0, 1,2 and 3 only
5. Repeat step 3 and 4
6. Now network only sees node 1 and 3
On the LED scroll on the DeviceNet Comm Module I see code 78, 5, and 4. Before the power cycle, I only see code 77, means mismatch data type according to the help manual. 77 went away after the power cycle.
This led me to believe that maybe the DeviceNet Comm Module is going bad. As Node 0 is the PLC that is on the same chassis as the comm module, if RSnetWorx sees the PLC intermittently then maybe the module is going bad?
Anyone encounter a similar issue with DeviceNet Comm Module? Any steps you have taken to further troubleshoot this issue?
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