text: <s>[INST] Powerflex 40 and 22-comm-e F081 on power up. Hello, I have been having a communication problem with several drives in control system after power is cycled whether it is off for 60 sec or 2 hours it doesn't matter I will get a F081 fault sometimes it will reset right off the bat by pushing stop button other times I could be there for 20 min waiting for the drive to indicate any power is going to the 22-comn-e and then when it does I may have too hit stop- button multiple times to get it to reset and communicate or the drive gets replaced and everything works as normal after replacing. I have replaced several drives out of this system that haven't been in service for very long with this problem so right now I'm am looking for a solution to fix problem if any. Thanks for the help in advance. [/INST] I have a couple of questions. How are your comm cables located in relation to your power cables? Are both your comm and power cables shielded, and shielded from each other? Are you actually losing comms or just getting the error? How long are you network cable runs? If there is nothing wrong with the physical installation, i.e. cable integrity, comm card, connections, etc, then I suspect noise in your comms lines. \\n </s>