Tuesday, March 26, 2013

Hunt for cheap steppers cont'd: VID teardown, datasheets



Steppers I mentioned in previous post came within a few days! They're not as small as I'd thought, but they are very flat. I bought them off of amazon by searching for "stepper motor gauge":
6 Stepper Motor Chevy AVALANCHE V8 5.3 8.1 2003-2006 Gauge Cluster Speedo Speedometer x6
$16.5 for 6, or $2.75 each.

The inscription says VID29-02P.

Well, I decided to take one apart.

They're geared steppers and you can see the end stop (top right) that prevents the gear from rotating and this stepper from being continuous. It has 315deg of travel according to the datasheet.

If you take it apart, you see that the four leads of the stepper go to the four poles of two coils of wire, switching the electromagnet on and off.

That's all there is to it!

Anyway.
Time to find a datasheet.
Here is one for a similar one, the MR series: http://clearwater.github.com/gaugette/resources/mcr/2010410104720473.pdf
(mirror)
which is where I get my guess of VID's "Angle of rotation of motor with internal stop" as equal to 315 degrees from.

Here's a note of the rather obscure manufacturers:
http://guy.carpenter.id.au/gaugette/blog/2012/05/25/buyers-guide/
For instance, in our case:
Hong Kong based VID also manufacture a range of similar motors. Their motors are black, and have a black model number starting with “vid”.
Well, anyway.
I also decided to buy (off of ebay) some less strangely shaped and hopefully easier to couple to stepper motors. They turn out to be cheaper too!


[x] img src, ebay iawoo

http://electronics.stackexchange.com/questions/60969/stepper-motors-stride-angle
28BYJ-48 – 5V Stepper Motor Datasheet
"New 1pc 5V 4-phase 5-wire Stepper Motor Gear Motor 28BYJ-48"
$8.72 for 4, or $2.18 each.

Those should get here in two weeks. It's nice to just order fun things ahead of time and feel like I am getting good deals.

That's all for now.

References

http://www.freescale.com/files/microcontrollers/doc/app_note/AN2974.pdf "Quick Start for Beginners to Drive a Stepper Motor"