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Hi Here's a question I'm about to ask Omron.. as soon as I can figure out who to ask.. It's complicated asking support.. their web email form doesn't make complex questions easy. Here's the question: Can the NJ CPU program a LinMot linear motor to make the "Random Sea"? The NJ has a mixed protocol.. Ethernet/IP and EtherCAT (CoE),  and claims to be a "Motion Controller".    I doubt Motion Control is available on it's Ethernet/IP line.. but the EtherCAT might be another story.   Certainly The Omron NJ is a Motion Controller for Omron NJ series drives.. However, how well does it work with LinMot? Here's the curve.  Imagine a LinMot Linear motor continuously moving, never really stopping, following a real-time, mathematically generated curve, moving positive then negative, at random frequencies and random amplitudes. Almost never repeating a motion sequence. looks something like this: Yet, after a while the motion history fully represents the spectral distribution of energy on the surface of the ocean. Spectrum analyzers can display it, and mathematics can define it..  I just have to make that sea in a model scale…    (Time scales by the square root of the scale factor) And keep the water in the tank: https://www.youtube.com/watch?v=SQd6YzBWVvI The big question is: Can the Omron NJ get a LinMot Linear Motor to do this? … LinMot thinks YES.. but, isn’t sure. Yes there are ways to “connect" LinMot to The NJ.. EtherCAT (CoE), Ethernert/IP but… there is nothing in the LinMot drive that can create or store a predesigned Random Sea .. Only a Motion Controller, generating real time motion commands, by running  mathematical equations, "on the fly” can do that.   If the NJ is a true “Motion Controller”, and the LinMot C1250-DS-XC is implemented as an “axis” by Symac Studio, which it is…       Then, there may be hope. Closed loop, PID feedback remains with the LinMot drive, with special settings in LinMot Talk … Homing might have to be done with the NJ .. or by Digital I/O’s What do the Omron experts out there think?  Can this be done? Thanks much, Regards, Michael

Hi... It's beginning to look like the the answer to the question "Can the NJ stream position data to a E/IP LinMot Drive" .. is NO    The NJ, using Ethernet/IP, can not produce Tag based data in constant cycles (which LinMot requires for streaming)  ...  CIP messaging doesn't look possible either.   However, over EtherCAT, the cyclic position data is constant, at 1ms, 2,ms or 4ms (with my NJ101-1000)  all within the range for LinMot streaming ... so they say... So now, I'm looking at using the EtherCAT port and the LinMot Drive C1250-DS .. an EtherCAT drive.. LinMot claims the drive will act as an Axis slave, just like Omron's G5 series motors. Which really work well when streamed with position data... Has anyone ever used a EtherCAT LinMot drive with the NJ successfully?     Thanks much, Regards, Michael

Using Ethernet/IP to stream position data to a LinMot Drive, may be quite difficult because the LinMot requires a precise period between data points.  I've been told PVA streaming has been done with the Rockwell PLC, but the Ethernet IP bus needs to be updated at regular intervals (the requested packet interval between the PLC and the drive), and the task/ladder that has the streaming command is also examined at those regular intervals. This sounds like a timed messaging system over Ethernet, to satisfy the LinMot's requirement for precisely intervaled packets, which would compensate for Ethernet/IP's general lack of precise timing between data packets.     (the preferred method is to use EtherCAT) Has anyone ever tried this.. ?   Please describe the method with a little detail .. I'm trying to see if an Omron NJ can stream PV or even just P ... using their Ethernet/IP port.     If Rockwell has done it successfully, I would love to know how...   Thanks much... Regards, Michael