We are having around 12 PF525 connected to 1756-EN2TR on DLR and the EN2TR is configured as Ring Supervisor . We are using to control also where in start/stop commands and the frequency , acc/deacc time cmmands are given as Output and Status and Speed FB is read as Status .
Now sometimes one of the drive goes in commn fault mode and the other drives after that also go in communication fault mode till the EN2TR port which also doesn't blink . When we give drive reset (Soft command via ethernet) all the drive reset and the system starts back normal.
Many a times that particular drive (mentioned above) stops responding to commands from the plc over ethernet but I don't get any comms failure . Only when I restart the drive 3 to 4 times the drive responds to the etherent commands.
We have tried changing the CAT6 cable between the faulty drive port and other drive port but still the problem persist. We even tried by replacing the Adapter but still the problem .
Also now when I remove the Ethernet cable from the drive port and other drive port , the rings become linear but there is no comms loss even with the same VFD and it operates perfectly in linear mode.
Please note that we are using CAT6 UTP cables and since the VFD are very near to each other CAT6 cable is outside the trunking and there is no managed/unmanaged switch in between.
Any suggestion what could be cause
Now sometimes one of the drive goes in commn fault mode and the other drives after that also go in communication fault mode till the EN2TR port which also doesn't blink . When we give drive reset (Soft command via ethernet) all the drive reset and the system starts back normal.
Many a times that particular drive (mentioned above) stops responding to commands from the plc over ethernet but I don't get any comms failure . Only when I restart the drive 3 to 4 times the drive responds to the etherent commands.
We have tried changing the CAT6 cable between the faulty drive port and other drive port but still the problem persist. We even tried by replacing the Adapter but still the problem .
Also now when I remove the Ethernet cable from the drive port and other drive port , the rings become linear but there is no comms loss even with the same VFD and it operates perfectly in linear mode.
Please note that we are using CAT6 UTP cables and since the VFD are very near to each other CAT6 cable is outside the trunking and there is no managed/unmanaged switch in between.
Any suggestion what could be cause
