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I have system with 1511F CPU and 3 Festo CMMT servo controllers, used as PositioningAxis with Telegram 5 (plus some IO). TIA Portal 15.1 As topic says, I am haunted with cycle time problem(s).
First I tested with single unit. I had other problems until I found out, what configuration and what commands work for me, but had no problem with cycle time, so I didn't pay any attention to it.
Now, when whole system was built, I downloaded full configuration and program to CPU and problems with cycle time started. When it refused to work, I made another test program with servos only and no F. With single unit, I got cycle times for first cycle 180-300 ms and normal 1-2ms. With 2 units first cycle jumped up to 500-800 ms and I had no success with 3. Playing around with the system and downloading actual and test programs with different configurations, I got to the point, when cycle with single unit was quite short. I got to this by first adding [empty submodule] to CMMT configuration and then removing it. I wanted to do the same with actual program, but after adding [empty submodule]s to all 3 servos, it worked! Peak cycle time was ~25ms and most cycles again ran at 1-2ms.
But after powering down I am back at 0. What can it be, what should I do?