Kinetix Torque Control

[chawkey]

Hello,

I have an application where 80% of the time, an operator will be needing to issue very accurate MAM or MAJ instructions to a Kinetix 5500 servo. This works exactly as expected when setting the drive configuration to position loop.

However, there are times when they need to jog the drive but hold a certain force (torque, current, whatever). That is where I learned about SLAT control, and how it might be my best option.

But in order to use SLAT, I have to set the servo to velocity control.. which is fine except for the fact that all move and Jog commands are now off by 5-10%. For instance in this configuration, a move to 20” would stop at 18.6”. This would be unacceptable.

I also know that you are able to switch between the two modes via SSV’s , but in order for this to work, I have to reconfigure the drive to be back in a position loop by default, then I can “degrade” the control to velocity for SLAT control while running. But doing this removes access to the SLAT configuration parameters in SSV’s (they are only valid parameters when configured to velocity mode). So I’m stuck spinning my wheels here..

The application is not a typical winder application, there will be no web breaks, so maybe SLAT isn’t necessary? Can I just simply keep the servo in position loop, issue a MAJ but perhaps change some torque parameters to hold a torque when presented with a mechanical limit? Now in this mode, I honestly don’t really care what speed it goes at.. only that it is accurately holding a certain force.

Any thoughts would be appreciated. I feel like I’m stuck between a rock and a hard place with my perceived options, and calling Rockwell is my next step after this.

Thanks all