Choosing Hardware for Project

[lueivind]

Hi,

We are making an automated threading/cutting machine and are having problems deciding what PLC hardware to use.

Things the PLC need to control;

- Precise position control of at least 3 servomotors.

- Some basic controlling of lights, pneumatic cylinders, etc.

- Some kind of HMI, probably a touch screen to choose different parameters.

- We have a programmable turning tool that only takes ASCII commands through RS-232. This is what we've been having the hardest time with. We'll need to store between 20-30 different ASCII commands somewhere and be able to send the different commands to the turning tool. There will be no PC connected to the machine after delivery.

Our experience on the subject is very limited. We are students working on a Bachelor project and kind of have to learn as we go. Any help will be highly appreciated.

Thanks.

 

[califflash]

The processor would depend not only on the io but the complexity of your program and the response time you require. Also whether or not you want embedded Ethernet or not and of course cost.

The processor selection guides from allen bradley are very helpful.

 

[lueivind]

The processor would depend not only on the io but the complexity of your program and the response time you require. Also whether or not you want embedded Ethernet or not and of course cost.

The processor selection guides from allen bradley are very helpful.

But just looking at the problem with the ASCII code, is this a common function in PLC's?

 

[jmsmoreira]

Yes you can send ASCII messages from a PLC.
I personally prefer Allen Bradley PLCs for that type of jobs, but I believe you can do it with any brand of PLCs

 

[califflash]

You should be able to send an ASCII message through a local serial port, if the processor has one, or through a module. I know the point io system has a module specifically for this purpose. I have never had to do that so maybe someone more knowledgeable can speak up. Ab should have some documentation in the literature library or on the knowledge base.

 

[shooter]

look at beckhoff, specialised in motion, or lenze, they make these motors.

 

[Highland Controls]

As Shooter pointed out, this is a motion application. You should choose a motion controller, not a PLC. What brand/model of controller are you currently using?

 

[JRW]

Step 1
Are these just point to point moves? Or are they coordinated in which they follow each in some way?