In what way the frequency of digital pulse affect the stepper motor funtion. I want know this because i can send digital pulse through my data acquisition card at rate of 100Hz. I want to run bipolar stepper motor..

  • \$\begingroup\$ Sending pulses thru a data acquisition card sounds odd. Data usually comes the other way unless the card is a multipurpose card. \$\endgroup\$ – russ_hensel Dec 21 '11 at 19:55
  • \$\begingroup\$ ya its multi function card only.. that is one part of my project \$\endgroup\$ – vijay Dec 22 '11 at 2:08

You have to look at the datasheet of the stepper. There is usually a maximum step rate, and sometimes maximum acceleration/deceleration requirements. Those of course vary with load drag and inertia too.

When working properly, a stepper moves exactly as driven. You sequence through 10 steps and the shaft should rotate the angle for 10 steps. However, this is generally open loop, so there are constraints within which you have to operate if you want to be assured the stepper really did what you commanded it to do.

The faster you sequence through the steps the faster the motor turns, until it looses lock and then it will usually just sit there and vibrate.

  • \$\begingroup\$ i gonna use 1.8 degree step stepper motor. For that i can give only digital pulses at the rate of 100Hz that means how much rpm i can get \$\endgroup\$ – vijay Dec 21 '11 at 18:37
  • 2
    \$\begingroup\$ @vijay - If you are stepping 1.8 degrees at 100Hz it will be (100 * 1.8) / 360 = 0.5 revolutions per second (or 30 rpm) \$\endgroup\$ – Oli Glaser Dec 21 '11 at 20:30
  • \$\begingroup\$ is there any circuit to give pulse without using daq... if available then can u please the send me the circuit...........i dont want to buy it instead i am interested to make my own circuit .. any help is greatly appreciated \$\endgroup\$ – vijay Dec 22 '11 at 13:19
  • \$\begingroup\$ I don't know what a "daq" is but you would usually drive a stepper motor with low side switches or possibly H bridges, depending on how the windings are wired together. \$\endgroup\$ – Olin Lathrop Dec 22 '11 at 13:54

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.