Tuning servo motor problems

I have a PCI 7344 connected to a UMI and a Ecodrive amplifier, with a linear modul and servo. Feedback is a incremental encoder 16404counts/rev (400counts/mm). When i try to autotune, the servo motor goes berserk, so I have to manually tune it with "Step response".
I am able to get a nice response curve according to "Understanding servotune" but the problem is, curve starts at -50mS? and at 50mS it seems stable, but settling time is indicated to be 500 - 600 mS, and when i use "wait for move complete.vi" it waits about the same period before it returns "move complete". I was expecting/hoping for 50 - 100mS settling time. How to tune this? I run position mode and there is no problem regarding velocity, acceleration and position feedback, the only
thing is that settling time is to long. I have no following error. Is there any other way to get a signal exactly when a position is reached.

Hi, thank you for your answer.
I still have problems with this, so here is some more questions.
1. I am getting a perfect curve on the step response, similar to attached picture (1), only with shorter time scale. The step response report under the chart that settling time is 500-600mS, which is settling time (<100mS) and steady state (>400-500mS) together. This period seems to be the same that i am experience with "move complete.vi".
I have Kp=7 Kd=14 and Ki=1, and i have tried to adjust these values but this is the best i get.
Does the loop need that time to determine that move is complete?
2. The move i want to do in my application is a movement about 20000 counts (50mm) in 130mS, wait 100mS and return to start in 130mS, this is possible if I use
software delay and start return move before first move is settled according to "move complete.vi" But this generate a increasing stop position error each move if I loop this sequense with 100mS rest time. These timings should be possible with the hardware I am using. Any suggestions?
3. I have set the driver/amplifier in velocity mode (incremental encoder feedback), how is that compared to torque mode in the driver in this case?
4. It is possible to get a second feedback from the drive (torque, velocity or position from an analog output) but this is 8 bit and less accurate than encoder. I also have a second external encoder for precision measurement and a force cell, but they are only active parts of the range to the servo (under the desired move) is there any other way i could set this up?
Regards
Attachments:
153.gif ‏29 KB

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Tuning servo motor to withstand external force of another servo motor

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From where in the UMI flex 6c I should give enable to servo motor amplifier/driver.

I am using ADS 50/5 maxon amplifier to run the maxon servo motors with Flex 6C. The problem I am facing is that, How to enable the amplifier so that it works only when desired. I have tried by connecting the enable to the inhibit output but it is not working. before connecting to enable Inhibit output is showing 5v but as soon as I connect it , it drops to 1.5V. I am giving encoder feedback to 6C. Motor runs when I directly connect enable to the power supply, but then it runs continuously. Can anybody suggest me about the correct connections.
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"It’s the questions that drive us.”
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FYP.vi ‏253 KB

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Como zerar o indicador LV que lê o um sinal de um resolver de um servo motor e a posição de um transdutor linear?

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Why does not my servo motor work?

Hello all,
I can work my servo motors, so I have two questions.
Firstly, I'm using PXI-7340 & UMI 7764 to control AC motor on servo motor (TAMAGAWA SEIKI co.),
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Can I connect UMI to the motor correctly?
Now, I connect encorder signals with changing differential line driver (motor driver) to TTL (UMI) using quadruple differential line receiver.
Is it right?
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Attachments:
TAMAGAWA SEIKI motor&driver.pdf ‏3063 KB

Thank you for your reply.
The "does not work" means that the motor doesn't move with servo type.
In MAX, there is no error when a target position is less than 999 in 1-D Interactive, but doesn't move. When the target position is more than 1000 and I click "Apply" and "Start", error ramps of "Motor off" and "Following error occurred" are red. And the motor doesn't move.
I thought that firstly signals of encorder have been wrong because the motor have not moved with stepper mode of closed-loop and feedback of encorder.
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Wiring of all is "STEP", "DIR", "AO", "ENC A, B and Index bar" respectively. In MAX, type is servo mode, feedback is encorder, kinds of limit switch are not used.
I supply it if you need the other setup of wiring or information.
Regards,
Megumi

Tuning servo motor problems

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