Suggestion for a stepper/servo system for project

Hey guys this site is an awesome blessing for me. I am trying to get back up to speed with PLC program and I have finally decided on a home project to get going to do so. Its based on a suggested project at the work place that is unlikely to happen but I thought it would be great for me to do on my own on a small dumbed down scale.

Here is the project I would be trying to pull off.

http://www.fusion-inc.com/automat1.htm


I went to school for automation but it was a new program at the time and we never quite got to incorporating servo motors or stepper motors in programing. I would be using MicroLogix 1000 and the free software.


I know servo motors are generally more common in manuafacturing enviroments than stepper motors. I know servos are used more for high torque situations. But the point is to get real world programing experience.

So the which leads me to the point.

What type,size system would you recommend for the above application.

And 2. I know little about these except there needs to be a motor and a controller or drive. So can anyone recommend a specific small scale combo(preferable Allen Bradley) I can get used on ebay for dirt cheap to incorporate with my Micrologix 1000?

Thankx

Look at step and direction program examples.
Don't know mass and gearing, so I need to guess. A 1200 ounce NEMA 34 motor should do.
Drive:
http://www.automationtechnologiesinc.com/products-page/gecko-drivers/gecko-driver-g23v
Motor:
http://www.automationtechnologiesinc.com/products-page/nema-34/nema-34-12-dual-shaft-with-flat
Supply:
http://www.antekinc.com/details.php?p=475

Definately have a go at step and direction type of stepper control, especially if you already have a ML. Ebay's full of gear so surf there 'till you get what you want.

http://www.ebay.com/itm/Parker-Comp...208?pt=LH_DefaultDomain_0&hash=item19d281c868

We still use a lot of stepper stuff as quite often you can't beat the cost.

Thankx. Does the drive need a seperate power supply or just 110V to the wall will work? Does my PLC need to except AC for inputs with this drive?

The stepper drives will require DC inputs. Some use 5v, some 24v. The drive itself will generally require 120v. The PLC will need to have a high speed output for the step pulses. If you want feedback from an encoder you'll need a high speed input. AMCI has all their docs available on the web:

http://amci.com/documents.asp

Kurt

Does a Micrologix 1000 have high speed inputs?

Inputs 0-3 support the use of a high speed counter (HSC) This is limited to controllers with DC inputs. According the the specs the absolute maximum frequency (with a 50% duty cycle is 6.6KHz). Later controllers like the 1100 have much higher rates. What I didn't see were any specs for high speed outputs. You'd want one for the stepper pulse train.

Well I bought the combo in the link of ebay you posted. I hope its gonna work. I would assume if the 1000 excepts high speed inputs it should have high speed outputs.

If it doesnt will it not work at all or just not be accurate?

You're pulse train output speed can't exceed the maximum frequency of the output. Hence, the speed and accuracy is limited to that and determined by the number of steps per revolution of the stepper. The AMCI is configurable via dip swtiches. If the max freq. was 1KHZ (cycles per second) and the stepper were setup up to do 1000 steps per rotation then effective max speed would be 1 rps or 60 rpm. All other things being equal your stepper would be accurate to 1000/360 degrees or 2.8 degrees (per step).

You might surf ebay for a bit and see if a ML1200 or 1500 pops up. They both have 1 (1200) or 2 (1500) 20KHz outputs. Just for reference go to http://literature.rockwellautomation.com/idc/groups/public/documents/webassets/browse_category.hcst

and search for the Micrologix selection guide which gives a good overview of the whole family.

I think I saw a 1500 on ebay for $99. with some expansion I/O to boot.

Read the above document before buying though to be sure you're getting what you want.

I have read the above documentation. I unfortunately do not see anything that states if I can use a servo motor with the Micrologix 1000. Nothing about if the outputs are high speed. The 1200s and above do. Unfortunately I already bought the 1000 and I am on a 12 an hour budget.

How can I find out for sure as Allen Bradley doesnt seem to give any support in my situation? I am just doing a project for self training. I will probably do a drink mixer with a rotary table to line the glasses up with the diferent nozzles to practice programing for motion control. It doesnt need to be very precise. Just within 1/4". I just need to know if it is going to work or if I have to sell the 1000 and get a 1200.

Can anyone help please?

If they don't state it, then they probably don't. If you do have DC outputs you may be able to set up a pulse train output yourself. (Which in itself would be an interesting task). You just won't get any speed.

Can someone look at the documentation for the micro 1100 to make sure it supports servo drives. And will the free version of RS LOGIX work with the 1100?

Skiroy said:

Can someone look at the documentation for the micro 1100 to make sure it supports servo drives. And will the free version of RS LOGIX work with the 1100?

Click to expand...

The 1100 has two high-speed outputs (40kHz on newer models) for stepper/servo control. I've used it for exactly this purpose and can vouch for the functionality.

http://literature.rockwellautomation.com/idc/groups/literature/documents/pp/1763-pp001_-en-p.pdf

I would highly recommend that you download the user manual for the 1100 and read all about the PTO/PWM instructions; these are the ones you'll need to utilize the high-speed outputs.

http://literature.rockwellautomation.com/idc/groups/literature/documents/rm/1763-rm001_-en-p.pdf

And yes, the free version of RSLogix does work with the 1100.

I'd second that the ML1100 works with a stepper. (Servo is a different animal all together). I just finished a project using one an AMCI stepper drive driven by step and direction signals and reading position back via an encoder connected to the high speed inputs. The attached is a quick start guide that may help you.

I would assume if the 1000 accepts high speed inputs, it should have high speed outputs.

Click to expand...

No, it is a beginner's unit, no high-speed outputs, and no analog inputs or outputs.