Stepper Motor

[JDR04]

I'm hoping somebody can advise me as to what equipment I should buy to experiement with a stepper motor.

I'm under the impresion I should get a BIPOLAR stepper motor with a driver board. They look relatively cheap on EBAY so I would like to have a bash at it. Its nothing serious at the moment.

Any suggestions on drivers,motors and flowcode5 information will be appreciated.

Thanks a lot folks....JDR04, John

[Benj]

Hello,

It really depends what your after.

I have driven stepper motors using just NPN transistors such as TIP122, they work well and are cheap but you are limited to full stepping or half stepping.

If you need accuracy then I have also used the EasyStep driver boards from eBay which work very well but you have to wait for them to arrive. The drivers use microstepping so you get a very high resolution on the output shaft.
http://www.ebay.com/itm/EasyDriver-Shie ... 5d40fcd940

[JDR04]

Thanks benj, appreciate the info.

Can I use any bipolar stepper motor up to 12V?

Thanks......John

[Benj]

Hi John,

With steppers it's down to the gauge and resistance of the coil that dictates the amount of voltage/current the motor can handle. I normally over voltage steppers i.e. a 5V stepper can be driven at 12V with no issues as long as you take certain things into consideration. Driving a 5V motor at 12V gives you more speed and more torque.

1. Never leave current flowing through a stopped motor, as soon as you stop stepping remove the voltage from the motor coil or you will burn it out.
2. Try and drive the motor as fast as you can get away with, the slower you go the longer each coil will be powered which again will cause strain. Too fast and the motor will vibrate rather than rotate.
3. If you do need to go slow then maybe consider removing power in between steps so as to let current flow only long enough to move the motor to its next step position.
4. If you want the motor to go very fast then consider half stepping or micro stepping. Stepper motors cannot go from 0 to full speed in a single step, ramping the speed up and down is a good technique.

If you need the motor shaft to "lock" in position for any period of time then you will need to keep the motor coil powered so in this case I would not over voltage the motor.

When driving stepper I have used timer interrupts in the past. To change the step speed you simply alter the rate of the interrupt. The interrupt checks to see if the motor needs to step in either direction. If no step is required then the motor outputs are disabled.

[JDR04]

Thanks Benj, any chance of providing a small example as to how you use the interupts please.

Thannks again........John

[Steve001]

Hi JDR04,

I use cnc4u for stepper motors and parts

http://cnc4you.co.uk/

Steve

[JDR04]

Thanks steve001.Always useful to have these guys in your favourites.....John

[Benj]

Hello,

There are some examples here which should help.
http://www.matrixtsl.com/wiki/index.php ... tronics%29

Let me know how you get on.

[JDR04]

Thanks Benj, will have a go and check it out.

Thanks for all the help.........John

[dazz]

Hi
AS benj says it all depends on what you intend doing, heres a couple of links, the only thing to note if you use the sites below is delivery can be a while, some stuff comes to the uk in 4 days sometines 60 days, but for the cost i dont mind the wait.
the advantage of the first link is you arn't moving a heavy stepper and it takes up hardly any bench space, also make sure if you buy you just buy items with free shipping


These will suit you for testing, and cost almost nothing
http://www.aliexpress.com/item/New-5V-S ... 105.nFfap7


I have used these in a boxford TCL125 cnc lathe, work well
http://www.aliexpress.com/store/product ... .91.ExVdIt

Regards
Dazz