Rockwell Automation 2090 Ultra3000 Servo Drives Integration Manual - Manual (Page 153)

Publication 2098-IN005C-EN-P — March 2008
Minimizing the Effects of Feedback Signal Loss 153
Interpreting the Results
Once the actual position and velocity error excursion limit values are
known, you can adjust the default Following Error Limit/Time and
Velocity Error Fault Limit/Time settings to be just above these actual
application extremes. This makes sure that any feedback loss events
causing abnormal position and velocity error amplitude increase are
detected and addressed by the drive in a timely manner.
In this example, the worst case Position Error is greater than 5000
counts, for around 32 ms, and the worst case Velocity Error is greater
than 22 rpm, for around 8 ms. The position and velocity error limit
settings in the Faults branch can be adjusted, according to these
observations, to 5000 counts for 40 ms and 50 rpm (or 1% of 5000) for
around 15 ms, respectively. The settings take effect as soon as they
are entered.
Ultraware Faults Branch
The new position and velocity error limit settings are significantly
lower than the default settings. Once the system is operating with new
settings in place, no nuisance faults should occur. If faults E19 or E24
occur during normal system operation, the excursion limit values were
not accurately extracted and the appropriate steps need to be
repeated.