Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: jhonilson on September 02, 2007, 01:27:27 PM

Title: Problem with my steeper motor...
Post by: jhonilson on September 02, 2007, 01:27:27 PM
  hi. i have a steeper motor with these specifications:
 - 5.6 cm Diameter  (56 mm)
 - 3.5 V/Phase (i do not know what that mean ..! , it will be that i need 3.5 volts for every bobin?)
 - 1.4 A/Phase (the same question..?)
 - 1.8 Deg/Step
 - Company is ASTROSYN    http://www.astrosyn.com/stepper.html  I have not the model of this. This motor was in an old printer. Is heavy.
 
   My problem is that i am trying this motor with a single h bridge with lm386 (similar http://www.todomicrostamp.com/pocket_projects.php?proyecto=4) and this h bridge is warmed up. I used 12 volt for h bridge and the motor. This h bridge support until 12 volts.  I need to know what h bridge is right for this motor (1.4Amp)?? I see a component called ULN2003 but i believe that it support 500mA only.

THANKS
Title: Re: Problem with my steeper motor...
Post by: hazzer123 on September 03, 2007, 06:45:32 AM
A stepper motor is driven differently to a normal DC motor, you have to charge the coils in a specific sequence for it to turn. In order to do this, there are many schematics on the web using microcontrollers or even logic gates.

A/Phase is the amount of current each coil can have when turned on. V/Phase is the voltage for each coil.

Harry
Title: Re: Problem with my steeper motor...
Post by: Ro-Bot-X on September 03, 2007, 11:06:08 AM
How many wires?
4 wires = bipolar stepper
5 or 6 wires = unipolar stepper

Bipolars can be driven with H bridge but unipolars no. Try using an L297 stepper coder and a L298N H bridge (up to 2 amps continuous, 3 amps peak). The L297 will generate the proper sequence for the stepper to run and needs only2 pins from the MC: one for steps and one for direction. A third pin can be used to select full or half stepping.
Title: Re: Problem with my steeper motor...
Post by: jhonilson on September 03, 2007, 04:12:00 PM
     My motor is Bipolar (i forget mention it). i know how work the stteper motor ( the diferent sequences). My problem is to get a good h bridge for that.
      I read the L297 datasheet and not see where says 2Amp output or perhaps i not know read this specifications. I will try it anyway.
  Thank you very much