Connecting and programming omron plc with ac servo motor


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I`m currently doing a project involving the Omron plc model CQM1-CPU43-E using programming console model PR001 and ac servo motor driver model R88D-UEP04H, ac servo motor model R88M-UE10030H-S1, connector terminal conversion unit model XW2B-40F5-P. I try to design a 2 axis robot using this component by using PID control of the movement of this robot.

My problem is I connect the control cabel model R88A-CTU001N from the servo motor driver to the connector terminal conversion unit and I solder myself a cable connecting the connector terminal conversion unit to the pulse I/O board of the plc. I connect the pin 15 and 12 of the port 1 of pulse I/O board to the 24 V power supply. Then, I connect pin 13 to pin 3 and pin 14 to pin 1 of
connector terminal conversion unit. I do not know whether this connection is correct for a 24 V power supply, please help me.

After that, I try to program the plc with function puls(65), there are P, C, N in this function. What do these means and how to program it. I had the same problem with function sped(64), where I do not know how to program P, M, F.
Lastly, how to combine these function with PID control. Can someone please show me how to do the ladder diagram, give me some example. In addition, do I need to set the PC setup in order to program these function?

I suggest you to connect with Omron USA site, "" , then follow links to "Support" then "Knowledge Base" or "PDF library".

There are all the manuals for Omron devices (PLCs, Servos, OP, and so on), and you'll find the informations you need, from wiring diagrams
to programming examples.

Been a while since I've used a CQM1 & Omron servo drive, but here's my 2P worth. (from memory as I'm at home)

PULSE and SPED pretty easy to set up and use. P,C and N are port specifiers and Control word location and no. pulses. With SPED, P is port
spec, M is output mode and F is Freq. These are all well described with examples in CQM1 programming manual section 1. Also available here:-


and are the only functions you should need (+direction input to servo) to get motors running.

Check manual about voltages, big mistake I made was to connect 24V to servo pulse input ports and blew them. They needed 5V. Not sure if all
Omron servo drives are the same, and it was well hidden in the manual.

To use PID it should be mapped (in Syswin use Project/function mapping) into the PLC as it is not a standard function. I usually replace
AFST(17). If I remember correctly, SPED can be adjusted continuously, so could be used in PID loop but PULS cannot be affected once started
unless apart from being cancelled.

Drop me an e-mail at [email protected] and I will dig out my records when I am back at work and try and give you some more useful help.



Nick Marchiori

I developed a similar application but with 1 axe. Anyway i didn'u used the PID control because omron says too slow. So using PULSE functionyou need to tell to the Brushless driver how my step / mm ort what ever you want to move (the unit convertion from resolver / unit is done inside the driver with parameters typical 8192 pulse per turn on a omron motor). Anyway you need to perform a calculus of how many steps you want to move and the speed , the direction is given by using CW or CCW out. You need to have a card for resolver installed onto the CPU and a card for the pulse train too. I do not remeber the order codes cause some time is past. So you use the pulse train to tell to the driver how much and how fast and direction: The frequency of the pulse train is proportional to the speed of the motor, the number of pulses is the pulses of the brushless motor and direction is CW or CCW.

Be sure the speed if not too fast and setup the cards in order to do not loose pulses from the resolver. Plus be carefull with SPEED when to stop it because i had some difficulties while the machine was in manual because the motor keep going and a very very slow speed but at the end i sort it out. Remember to rewrite speed 0 and pulse 0 to stop at the end or
something like that.

Best Regards Nick Marchiori
Venice Italy

PS: if you do not need too much precision use the 3g3MV inverter for common elettric motor it's easier.