text: <s>[INST] Fault Kinetix 6500 Hello my friends. I have a problem and I hope you can help me. Why does a Servodrive remain in Stand by status? and it cannot be corrected, the only way is to turn off the entire machine (including PLC) and only then will the servo drive return to its Running working state. And it is not just 1 servo drive, it is random, it should be noted that the machine has 120 servo drives controlled by 2 L73 processors and 2 1756-EN3TR modules. And this happens when we turn off a drive rail for various reasons, after cleaning, changing a servo drive, etc., and when we reconnect the control power of that rail, there is 1 servo drive (it can be any) that starts in the STAND state. BY and it is impossible to return it to its working state and the only way is turning off the whole machine or the PLC. It should also be noted that it does not always happen, there are times when it starts up fine, but when it happens, a lot of time is lost to make the machine operational again. The ethernet communication is also correct, since I PING the IP of the drive in STAND BY, and it is correct. I have to point out that the 1756-L73/B PLCs have fw 21.011, the 1756-EN3TR/B modules have fw 10.010, and the Kinetix 6500 servo drives have fw 3.003. Thanks so much. [/INST] Hello GAAM With a large servo drive architecture like yours it is hard to identify the source issue without being on site. Because there are a number of things that can go wrong in a large system if not correctly managed. Basically, the standby issue means that the drive is waiting to receive configuration data from the controller. it is a communication issue at startup, So we have 4 possible sources of this communication problem, the controller, the ethernet Card, the switch or the drive. 1st : What is the Logix Version , and Drives FW used in your system? 2nd: Does this issue as always exist? or is that recent? have you made any changes on this machine (new HW, network changes...etc)? 3rd: Connect with Studio 5000 and check the standby drives information's and status, look also at the extended fault information's. look at the fault history to see if there is not multiple faults cascaded. 4th: What is the CUP (Coarse Update Period) of the Motion Groupe. 5th: does the issue occurs only on a specific group of axes associated to one of the EN3TR ? 6th: Where Time Grand Master is located (EN3TR's or Controller or somewhere else ?) 7th: What switch are you using? 8th: When you turn off the Drives Power supply control. Does that power off the switch aswell ? Thanks for the feedback Regards \\n </s>