ctrlX CORE to ctrlX DRIVE with Open Loop Velocity Mode

[tommorassini]

I'm making a test for a customer that is actualy using a Turck Codesys EtherCAT controller.  I was hoping to show how to do it with our ctrlX CORE as an example and I have a few problems.

I do have the drive configured for Open Loop and everything seems okay with that so far.  The problem is that it appears we only think about Position Control with the ctrlX CORE.  When setting up the "Profile" in the CORE web interface there only seems to be mapping for the Position Command.  I don't see a way to map Velocity Command S-0-0036.  Also I would have expected something in the Axis definition for this type of axis???

From the PLC Engineering side I hoped that the typical "MC_MoveVelocty" would have automatically written to S-0-0036, but I don't see this Function Block.  I tried "MC_Jog" and here too I assumed it would write to S-0-0036, but I don't know if that's exactly how it works (I'm guessing not that it uses Position Mode and it creates the Velocity Command from that).   Something does seem to happen, but it's very strange.  With a postive Jog the value started at a small value and kept incrementing up to 1,000 (I programed 25 RPM).  When I tried a Negative Jog the value kept incrementing up to 214783648.

How do I do this?

Another issue is the customer actually wants to control the drive similar to a typical Fieldbus application with Control/Status Words and directly issue a Velocity Command.  I couldn't see how to do this either.  The S-0-0134 to Enable the drive seems to want to come over from the "MC_Power" Function Block.  Likewise I coulnd't directly write to S-0-0036.  

From ctrlX DRIVE Engineering I deleted S-0-0134 & S-0-0036 from the MDT and then I was able to directly write to both parameters from the PLC.  

How do I do this properly?

[CodeShepherd]

You have to differ two possibilities of velocity mode:

1. Velocity control mode via the ctrlX MOTION (always closed loop):
   Here always the the control word and velocity setting is handled via function blocks (e.g. MC_Power, MC_MoveVelocity). As well as only position command value is sent cyclically and the motion kernel internally is calculation the velocity profile (like MC_Jog does). So it also expects a encoder feedback value.
   
   
2. Velocity control mode as field bus device:
   Here you cannot use the ctrlX MOTION. Everything is handled by your own e.g. via the PLC. You will have to add the fitting parameter to the cyclic data channel and set the modes correct in the drive. Also control word and velocity setting has to be send user.

[tommorassini]

Thank you for the suggestions.

1.  I would ask that this possibility is encorporated.  Running an Asynchronous motor without encoder feedback is a very common requirement on many machines.

2.  Can you please provide more details on how to do this?  In my first post I detailed the trouble I had in trying this.  The issues are both how to Enable the drive since S-0-0134 is required in the MDT, but it seems to be permanently linked to "MC_Power".  As for the Velocity Command I don't see how I can properly write to S-0-0036 cyclically.  Basically I'm asking which parameters should I be using for Enabling and Commanding the Velocity?

[CodeShepherd]

Moved to corresponding sub forumctrlX MOTION.

1. We are planning to have a feature to be able to control drives with exclusive velocity operating mode in ctrlX MOTION app version 3.4
   
   
2. It is not possible to use the ctrlX MOTION and control the drive via the PLC at the same time. So the axis and especially the axis profile needs to be deleted in the ctrlX MOTION configuration.