sdefisher Posted September 14, 2022 Posted September 14, 2022 I have a motor that is tripping a fatal following error fault when the observed following error is well below the Motor[x].FatalFeLimit. I've used the plot/gather system to prove that the following error is 25% of the limit when the FeFatal error kicks on. This only occurs when using a handwheel (master follower) or jog commands/jog ribbon. If I grab the axis and push it by hand, it trips the FeFatal error at the correct limit value. The motor jogs fine with the limit set to 0 (disabled). So I know it's not a drive fault kicking the motor off. Any reccomended troubleshooting steps? Quote
steve.milici Posted September 15, 2022 Posted September 15, 2022 Make sure the phase frequency is greater than the servo frequency and gather on phase. I suspect that the jog ribbon and master following could be producing spikes in FE that servo rate gather does not see. Quote
sdefisher Posted September 16, 2022 Author Posted September 16, 2022 13 hours ago, steve.milici said: Make sure the phase frequency is greater than the servo frequency and gather on phase. I suspect that the jog ribbon and master following could be producing spikes in FE that servo rate gather does not see. That did it. There is a very very short spikes in the feedback that is sub millisecond. My previous gather settings weren't fast enough to catch it. Looking into the wiring/feedback cables now. Is there a time component/setting to any of the feedback settings? Some CNC's have a time constant for controlling following error faults. Although I think that would just be a band aid in this case. Quote
steve.milici Posted September 16, 2022 Posted September 16, 2022 When using Position Following, large changes from the master may cause significant changes in the commanded velocity of the slaved motor resulting in your FE peaks. Use “Motor[x].SlewMasterPosSf” to mitigate this. When jogging reduce the acceleration values (Motor[x].JogTa/.JogTs) to reduce your FE peaks. Quote
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