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Hey y'all- I have an application that uses an Allen Bradley servo with a brake and a linear actuator to lift a plate vertically. While maintaining a position, the servo drive (Kinetix 5500) will occasionally fault due to over-torque.  I'm thinking it could possibly be due to mechanical issues i.e. bearings in the actuator but my initial thought would be that it would fault while moving up/down as well, so far I've only ever seen it fault while holding a position. This leads me to suspect that there may be something off in the control loop. I'm not involved in the setup but I know we use load observer and I reckon we use auto-tune. Other than that, I wonder if it's something to do with the brake. I also read about mechanical resonance in the manual which seems like a stretch but it could be contributing, the frame that the actuator/motor is attached to does vibrate a fair bit.  I'm familiar enough with basic motion control using Allen-Bradley and understand the basic concepts behind the servo/control loop. However I'm at a loss for why the servo/drive would spontaneously over-torque while maintaining a position.  How would you guys approach troubleshooting this further/solving this issue?  Many thanks!

So I'm having trouble writing a FBD within my current program for a slitting line. I need to keep a constant tension on my web as it is being recoiled onto our recoiler. I wrote a simple program using a sensor to read the growing rate of the coil to get a radius and I have feedback on my torque on the recoiler motor. The simplest math for this application without getting into anything too fancy should be Tension(lbs)= Torque(ftlbs)/coil radius. only problem is when its less than a foot then my calculation is thrown off and it actually shows tension goes up until it reaches the one foot mark then it seems to scale correctly. Do I need to scale something else? Any help on this would be appreciated.

Getting this error while adding MC_TorqueControl. I want to control torque from HMI value. Using R88D-1SN08H-ECT drive and R88M-1M75030T-S2 Ac servo motor with NX1P2 PLC. Newbie Here. Please support. Error    1    The Axis parameter of the MC_TorqueControl instruction does not support single-axis position control axes.    Program1 Section0    Row 6  

Hello  i installed an powerflex 70 into a CNC Mill machine, and its works fine over 1000 rpms, but below that RPMs its like the motor loose torque. i think could be a sliping problem. its some parameter need it to be changed?. or any special parameter that i need to look out?.    thanks for your help.   Regards  

Hi,  I'm new to TwinCAT 2 and i'm upgrading a long time design (hence the TwinCAT 2 reference), to read a more sensitive torque signal.  I'm using a Beckhoff CX1030 as my PLC Controller.  I needed to add 'homing' to my motor sequence and confirmed with Maxon, im using the function blocks correctly and in the correct sequence to establish my 'absolute zero'/'home' position.  The motor has an output to write to:  ControlWord, which tells the motor that the position it is sitting in is '0.'  My program compiles, it runs, it writes each function block, but it's not seeming to get back to the test run opMode, even though i tell it to and the function block performs the 'Write' function.  it's stuck at zero and not reading an analog input signal from my torque sensor.  so im getting an artificial torque reading through every test.   i think this is related to my tare motion.  I start the program, home the motor, get into profile velocity mode, tare my sensor, enter profile position mode, go back to position 0, then back to profile velocity mode, run a test, sample data, go back to 'home' or '0.'  I wonder 1st, is my variable not linked properly through the system manager?  2nd, i set a boolean variable to set the 4th bit to 1 in my control word write (setting the 4th bit high will set my current position to absolute zero), but did i not connect the program to the main sequence properly?  looking to read a valid signal again and see that my motor moves back to 'home' each time.  Do i not need to home the motor after the tare, since the tare nulls out the torque value after the tare? after this i need to program my sample period, instead of it being fixed, as it is currently written and then use my home position as my trigger to start sampling.... Beckhoff applications department is overloaded, currently and can't help and this is all beyond the knowledge of the general support line.  I've gotten fairly far, on my own, but of course, the project is under a time crunch.   Does anyone know twincat well enough to help guide me?