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Connecting a rotary encoder to the AKD-PDMM
I have an AKD-PDMM driving a motor with feedback, and I want to connect an additional rotary encoder. The one I have is a standard quadrature encoder. From the knowledge base articles, I see that it is (or was) possible to connect an external encoder to the X9 Emulated Encoder port. Is that still possible?
The KAS IDE dialog for adding an PLC Open axis makes it look like EtherCat is the only option.
What are my options for connecting this encoder to the PDMM?
Submitted by Eric Hoffstetter Wed, 08/14/2019 - 11:15
The PDMM contains an EtherCAT master controller and an AKD servo drive inside one device. All AKD servo drives (including ones inside a PDMM controller) have an X9 connector that support standard incremental encoders to be wired up to read the encoder external to the servo motor connected to the primary feedback port. In the drive setup screens, there is a Feedback 2 screen where you setup the resolution of the encoder. Once this is done, you can create a Digitizing Axis in the KAS IDE development software that is tied to this external encoder. Since we are only reading positions from this device and cannot command motion, a subset of our standard motion functions work with a digitizing axis including MC_ReadActPos, MC_ReadActVel, and having it be a master axis for a MC_GearIn or MC_CamIn function block. This is done over EtherCAT, because even if you have no other devices in your system besides the PDMM, internal to the device there is an EtherCAT connection between the master control board and AKD servo drive inside the PDMM. The EtherCAT master reads the external encoder position over EtherCAT from the AKD drive.
We have other pages on KDN that describe the process of setting it up at https://www.kollmorgen.com/en-us/developer-network/external-encoder-kas-pdmm-project/ and https://www.kollmorgen.com/en-us/developer-network/scaling-2nd-feedback-kas-ide/
Submitted by Joe Parks Wed, 08/14/2019 - 13:12