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jdemille
01-02-2006, 03:49 PM
How fast should I be able to move my steppers I thought I could get around 700-1000 rpm my data sheet for my steeper has up to 20 rps. My brain says take 20 * 60 sec for 1200 rpm. Now I’m using mach3 and gecko 201s. I can only make them move by setting the steps per to 20,000 and velocity to 10 this gives me movement about 75-100 rpm I guessing by the masking tape I have on there and a stop watch. Any other setting gives me sputtering or no movement I have the current resistor set to 1 amp.

Here are the basics of what I have.

Applied motion HT23-399
Gecko 201
24v dc @ 5 amps
Mach3

Any input would be great.

ger21
01-02-2006, 03:54 PM
What kind of machine, what lead is the screw, what are the motors rated (voltage and currentand torque)?

Steppers lose torque as rpm's increase. To get high rpm you usually need very high voltages.

jdemille
01-02-2006, 04:02 PM
No machine at all no lead screw. The motors rated at 12v i'm running 24 right now but plan on jumping to 48V soon but the specs on the motors say they where tested at 12V.

ger21
01-02-2006, 06:25 PM
12V motors won't spin very fast. Even with 48V you won't see a lot of improvement. Most people using Geckos use 10-20 times the motors rated voltage to get good top speed. Ideally you want motors rated 2-4 volts.

You might want to trty lowering your steps per inch in Mach3 to 10,000, increase the velocity and reduce the accel.

How are you getting it to spin? Jogging? MDI? G-code?

jdemille
01-02-2006, 06:40 PM
I was using the Jog Function i used g-code also. As far as the rateing goes i cant realy tell whats its rating is. the manufature lists everything from 2v to 40v they have torque curves showing 12v and 40v.

would uping the amps work? Right now I have it at 1amp


Jason.

pminmo
01-02-2006, 06:49 PM
Wire the steppers as bipolar parallel. Set your current to the 1.41A of the motor rating. Even above that you would get your best performance increasing your ps voltage as close to the 80VDC of the Gecko.

ger21
01-02-2006, 06:49 PM
Don't set it higher than the motor is rated. Do you have it wired bipolar parallel or series. Try wiring it parallel and using 1.4 amps. It should be able to spin fastest that way.

The HT23-400 and HT23-401 would work a lot better than the ones you have. Yours have a very high inductance, which is not good for hgh speeds.

http://www.applied-motion.com/products/stepper/motors/sizeht23.php

If you look at the chart, at 24V and 600rpm, your motor only has 37oz of torque.

jdemille
01-02-2006, 07:04 PM
Great thanks. I will try that I'm not going to be spinning anyware near that fast in real life I just thought I should be able to. .


Jason