PowerFlex 525 Unable to Completely Stop Motor

So were you in V/Hz mode prior to that?


Did you perform an Autotune?

jraef said:

So were you in V/Hz mode prior to that?


Did you perform an Autotune?

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Correct, we were in V/Hz mode prior. He put it in SVC mode and immediately the symptom went away. Unfortunately some other issues in my plant needed my attention so I'm not sure if an Autotune was performed post change.

On the 525 (all all Gen 4 IIGBT based drives) even if you use V/Hz, it's a good idea to do the Autotune if you want any reasonable accuracy.

My 2 cents.
I would implement a discrete start/stop signal or via comms to the drive and not rely strictly on the 4-20ma signal. While I do recognize the "sleep/wake" mode will deal with the lack of resolution effecting the low signal level (4mA) if you get a surge on the analog signal you could get a jump in the drive. If the discrete input is off then it won't matter what the analog signal is at, the drive won't start. Having said that I'm not a "drives" expert so I don't know what standard practice is but I use drives a lot in demo displays and if I had to deploy one in an application I would feel much more comfortable having a digital signal control the start/stop with the analog controlling the speed.
Again, just my two cents.