finding an appropriate (cheap) servo motor drive

[TedG]

I'm trying to implement position control for a brushless dc motor using a UMI 7774/7772. I originally purchased a driver from anaheim automation(http://www.anaheimautomation.com/brushless-dc-driver-mdc100-050101.aspx), however, as I discovered from a post here, that driver is not suited to my application because it is not bidirectional. (instead of having a +/- 5volts input to control velocity in both directions, the driver has a 0-5 volt input and a switch for direction.) My motor, also from anaheim automation, is a BLY171D-24V-2800 (http://www.anaheimautomation.com/manuals/L010228%20-%20BLY17%20Series%20Product%20Sheet.pdf).

I looked at the list of recommeded drivers on NI's website, but some of the drives I could not find, and others appeared to have far more features than I actually need. (Also, having already purchased one incorrect drive I'm a little reluctant to buy another without first getting the opinion of someone who knows the field.)

Can anyone recommend a basic, inexpensive motor drive that would work with my system?

Thanks very much,

Ted G

[Brian_Beal]

Applied Motion Products (www.applied-motion.com) has a good variety of stepper drives.  Any of the ones that have joystick input should work for you.  You can probably use your Anaheim motor if it is a stepper.

[BCho]

Hey Ted-

Brain has pointed out a good resource. We also have a resource on our web-page (Drive Advisor). You had mentioned that you saw a list of recommended drives on our web-site, is this drive advisor the same list. You had also mentioned that you had trouble finding some of these recommended drives. Are there any specific drives that you could not find? Also, what are some of the specs that you are looking for in a drive.

Let us know if this drive advisor or Brian's advice helps you find an appropriate drive.

Ben

Applications Engineering

National Instruments

[TedG]

Yes that was the same list that I found on the website originally. I was unable to find anything in the servostar series from kollmorgen; perhaps they are out of production. I was also unable to find even a website for the company Advanced Digital.

I'm trying to use a 24 volt dc brushless motor in the lab for some seismic research. The motor will be hooked up to a model structure on top of a shaking table. The goal is to limit the movement of the structure in an earthquake using the motor, a sprocket, and some roller chain. I doubt that the motor will ever make even one full rotation, but it needs to reach the target position determined by our control system quickly and precisely. I need a drive that will take a +/- 5 volt (or +/- 10) analog signal and run the motor at a speed corresponding to the voltage. It also needs to do the commutation, because I don't have enough axes free on the UMI to use two channels for the motor.

Thanks for all your help,

Ted

[Brian_Beal]

Applied Motion makes a servo drive also.  Do you have an encoder on your motor?

[TedG]

Yes, I have a 1000 line differential encoder. That much, at least, has been working flawlessly. Though I could not get the motor to run in the Measurement and Automation Explorer using the original drive, the encoder accurately indicates position. I'll check Applied Motion out.

Thanks for the help

Ted G