Need precision carriage positioning.

[pszczepan 2]

Hi ! I will make an aplication where PLC will be control carriage moving between four rows. At the beginning I wanted to use: 3-phase motor 0,55KW with gear, frequency inverter to set different speed - slower when it comes to special position and encoder to get info where carriage is. Someone recommend me servomotor . I have never used it - could you recommend me any websites where I can learn a little bit and what I should buy - what servomotor and other equipment?? to have possibility to control it (position and speed) from CJ1M - It is not yet purchased. Maybe you can recommed sth. different Thanks pawel

[gtsuport 61]

Check with your Omron distributor on the SmartStep servo. The SmartStep uses pulse input to control the motor. You could use a CJ1M-CPU2x series with the high speed built in I/O. Hope this will help.

[ParaffinPower 13]

If you've never used servo, go for Junma. I'd use CPU 2x or a CP1H for control. I've used Junma ML2 and it is excellent. [aside]does Junma make Smartstep redundant?[/aside]

[GEORGE_GR 0]

hi If you dont need fast movements there is no need to use servomotor. A good solution is the closed loop vector inverter f7 with the dedicate software for positioning. Otherwise do your job only with the plc and preset speeds. if you want sample code contact me!

[beegee 7]

depending on the speed you can even do it with a open loop inverter (we do it all the time with V7 alias 3G3MV) and the encoder on the PLC. The MAC in Barcelona, Spain has even some sample code for the PLC board to plug onto the V7 or R7. Your Omron representative should be able to get you those programs. But it is even easy to program without the examples. If you have a more dynamic system Junma/Smartstep can co the job with the standard PLS/PLS2 functions in the CJ1M-CPU2X. In case of a very dynamic system you can always take the Sigma II with a plugin board (MCW151 or NS300 NS500) Beegee

[pszczepan 2]

I do not need fast movement probably I will use inverter and encoder. Could you explain how works inverter with closed loop. In this case I do not need encoder to get position in my PLC? All setup what speed and where the carriage should stop goes direcly from inverter which is configured by itself software without PLC involving? It is just my thinking, what is the true? Thanks Pawel

[beegee 7]

If you don't want the encoder on your PLC, you will need a special positioning firmware in your inverter. The only problem is that after each power interruption or emergency stop you will have to perform an origin search. I would consider using an open loop inverter and close the loop on the PLC. You just vary your speed according to the distance to the target position. Works a bit like a classic motion controller but not that dynamic. You will need a dead band around your target position because with an open loop inverter you don't have torque at very low speeds. regards