No announcement yet.

Is there a way to test the drive output?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Is there a way to test the drive output?

    I have a SVA-2100 SureServo drive that is connected to a SVM-210 motor (no brake). I can run the motor back and forth all day long when the shaft is not connected to anything. I connect the motor to the ball screw mechanism and it will run a couple times and then alarm 09 - position deviation error. I jog the motor and it will not move until I physically start the rotation. I checked and the torque is set to maximum. however it seems that anything over 10% trips the drive. I removed the motor and ran the motor. Though I do not recommend this as a diagnostics option, I did grab the shaft and I can stop the motor and cause the trip. We tried another known good motor and same thing happens. This has been running for over 6 months with no issue. Today it doesn't want to drive anything. By the way the ball screw is fine, I can rotate the assembly very easily from end to end with no binding.
    Is the drive output bad? I do not have another drive to test, but we are going to order one. In the meantime, is there any test that can be done?
    I tried adjusting the motor tuning values and the best this does is delay the position error alarm.
    In a related question, I am trying to set-up a MODBUS read of all the P1 and P2 parameters into an array. All I seem to get is zeros. The data is formatted as integer 32 type, is this wrong data type? I use this same data type for reading individual parameters. Is it the 1D array? My MODBUS read instruction tries to read this as one entire block read (having to split up the reads as the maximum is 62 elements). I know the read instruction is correct as all other read instances in the same program work. But this is the only read instructions that try to fill an array.

  • #2
    If this has been running for months just fine then I would think it is either a wiring issue or hardware problem in either the drive or motor. Since you already changed the motor, that *should* mean the wiring is fine and the motor is not the issue. If it were a new drive, I would suspect parameters not set right before anything else.

    I actually have a drive do the same behavior as you have here, only mine was brand new and had the problem from the beginning. What I discovered was that the position mode was broken in the drive. I could run it fine in velocity mode, but as soon as I switched to position the drive would error with position deviation as soon as it got any kind of load on the drive. Tuning as much as possible only delayed how long before the drive faulted by a short bit. The only solution was a new drive, and the new one worked perfectly and is still in use. So one thing to test would just be changing the mode you are using and seeing how it operates in another mode.


    • #3
      Thanks Mike. Sounds exactly what this drive is doing. I even reset the drive to factory and then entered all the correct parameters to ensure nothing was corrupted. I know the parameters are correct, I have checked them at least half a dozen times! On another servo installation, I had the parameters get corrupted when we had a power outage. But on that drive (SVA-2040) I was able to factory reset and reload the parameters and that drive has been working correctly for over 2 years.
      I will try the velocity mode and see if the drive generates torque.


      • #4
        One other thing, you may have a bad phase on the drive. That can cause some interesting issues.


        • #5
          Originally posted by Adisharr View Post
          One other thing, you may have a bad phase on the drive. That can cause some interesting issues.
          Fixed. It was bad phase, but not on the drive. The wire in the motor cable was broken. You wiggle the wire and it would work fine, then wiggle the wire again and stop working. Wire broken at the cable connector. Spliced the broken wire and it works fine. Will order a new cable to replace and the spliced cable will be an emergency back-up.