NI 9514: velocity limit with SCAN Interface mode?

[Philippe_69]

Hello,

In my application, I use a CompactRIO 9074 chassis, a NI 9514 module and a AKD EtherCAT to control a brushless motor (AKM 23F), and I succeded to run it . But the problem is:

With the SCAN Interface mode, the motor can not exceed a speed of 51 rpm. If I try to give it a speed of 100 rpm or higher, it will stop in a few seconds and the state of AKD drive change into inactive for Hard Ware and Soft Ware. So I'd like to know if there is a speed limit with the SACN Interface ? (Is it because of the acquisition rate limit ?)  Do I have to go to the mode of FPGA if I need a speed of 6000 rpm? Thanks !

[Aurel.Co]

Hi philippe_69,

Thanks for posting your question in this forum.

I don't think your problem comes about Scan mode/fpga mode.

First, do you use softmotion and labVIEW real time module ?

Did you succeed to drive your motor in open loop with speed more 100 rpm ?

Best regards

[Philippe_69]

Hi Aurélien,

Thanks for your reply. Yes, I use SoftMotion and LabVIEW RT. Now I find that may be the wrong is due to "the programmed position error limit", because the motor always stop at the position of 1000 rev even I change its move velocity, and I got an error 70219 "The move stopped because an axis exceeded the programmed position error limit. Verify the feedback resource connections and/or tune your motor" when the move target is longer than 1000rev. But how and where to tune the motor ? I have tried to modify the parameter of "Limits => Position Limits => Maximum Position Error" via the Kollmorgen WorkBench, but it didn't work.

Below is a photo that shows the error.   

[Philippe_69]

Additional information: I tried to give the servo motor a speed higher than 100rpm, it could run but always at the speed of around 51 rpm.