View Full Version : Which motor is this???

02-22-2008, 08:01 PM
http://img141.imageshack.us/img141/3479/52980829on3.th.jpg (http://img141.imageshack.us/my.php?image=52980829on3.jpg)

I want to know if this is a Bipolar stepper motor??

This motor has got 4 wires & it is made in Thailand...
When i asked at the shop he just said that he got 2 types of motors
6 wired & 4 wired.

So tell me how physically the two types of motors that is Unipolar & bipolar motors differ???[/img]

02-22-2008, 10:54 PM
ask google "stepper motor" it will guide u.

any way
if Ur motor has 5 wires it can be used only in Unipolar mode ..
4 wire only in bipolar mode

with 6 ,8 wires it can be used in both modes .....

With 5 wires you CAN use it in bipolar mode!

using only 4 wires and leaving the common one..

02-22-2008, 11:19 PM
Its a 24V bipolar Nimebea printer stepper motor.

02-23-2008, 07:42 AM
Thank you

02-23-2008, 07:11 PM
With 5 wires you CAN use it in bipolar mode!

using only 4 wires and leaving the common one..

i think it is not possible to use unipolar motor in bipolar mode.

02-23-2008, 09:20 PM
It IS possible!!

02-23-2008, 09:47 PM
Sry there but 1 small doubt............

How do i know the angle of the stepper motor???

02-24-2008, 12:50 AM
1. Run the Motor. Count the number of steps.
2. Connect a battery to the stepper wires. It will move 1 step. Measure the angle.

02-24-2008, 01:20 AM
if u have more number of wires,u can drive the motors in any mode.its depends up on ur controller circuit.
imean bi-polar driver or uni-polar driver.

i need a favor from u.i made a uni polar driver using PIC16f84a and some mosfets.it worked for some time then failed.(i ended up with a nice HOT PIC).
regrading this i posted a query in CNCZONE.can u give me some more data to make it work better.here is the link

02-24-2008, 01:49 AM
Hi Firoz,
Couldnt make out much on the cncforum.
Can you elaborate? Also, your schematic will help.....

02-24-2008, 09:36 AM
my aim is to run 3 steppers(recovered from printers.not very small.)
there the motors iam using now.

so i want around some sites and collected data for a simple 3 in one stepper driver.and ended up with this design

i'll be using below current choper circuit instead of just resistors.

instead of IRLZ's i used VNP10N06(ST make)(as i had plenty of them).
and used only 5v for 24v motor.

so i made a prototype on breadboard and used MACH3 to test the setup.it worked but the result is uneven running of motor.i did some tuning,mean while the chip got and burned out.
now what iam thinking is,it burned out may be bcz
1.i haven't used the chopper for the trials.
2.the PIC lines can not drive the mosfet directly.

so can i just replace the ULN2803 with mosfets.i'll use 2 channel per winding.or shld i still use mosfet after the ULN.
and the uneven movement of motor is bcz of not using the chopper?

can u help me to solve these issues

02-24-2008, 11:42 AM
hi firoz,
I have done something similar, an Area gantry to be exact, but I used Transistors, it worked well, never gave me a problem.

I used Serial Port, and a 16F73. The steppers took 2A when I measured low side. I ran them @20V.

The circuit was simple and straight forward, though I used a Geared DC motor for the Z axis. For the record, the Gantry will drill, and mill, but the z axis would move a max of 10 cm.

Serialport>16F73/873/72>TIP122 !!! Eventhough the motors were 8 wire, i prefered to run it in Unipolar mode.

The uneven rotation might be due to the speed, and the voltage. Reduce the speed and check the motor.

Have you checked the waveforms, and the current the motors take??

02-24-2008, 03:31 PM
thanks for the info.
no i have'nt done any thing like that.imean waveform checking etc.
my requirement is simple smooth running stepper.bcz i want to concentrate more on my mechanical.
my driver has to be parallel port driven,as the software iam gona use is MACH3.
today i replaced the stepper with just LED,and their pattern (lighting patten) is really odd.so i think problem in the brain code(PIC)
can u suggest me some more PIC -parallel-circuit.
i have to keep the electronics as minimal as possible.that why i avoided linistepper.

02-24-2008, 05:20 PM
I have NOT worked with MACH3, so i dont know how the software communicates with the hardware.

Did you program the PIC, or did you just burn a hex file?
it has to be a program glitch. I still cant understand why they used two 16F84s, they can do well with ONE PIC of a higher pin count.

can you just post the code?

02-24-2008, 10:32 PM
i got the code from DAK's site.

there r 2 code.one is original and other for half step.the original worked a little(motor is vibrating a lot).and the other code is not working at all.
and the code is meant for 16f84 where as iam using 16f84A.

02-26-2008, 02:01 AM
You should not drive the Mosfets direct from the PIC controller. Some kind of 'bias resistor' is necessary, at the gate of the FET. ie., the gate MUST see some precise voltage level, Hi or Low to work properly.

02-26-2008, 11:31 AM
thanks i'll do that.

but after burning my 2 pics,iam really fed up with this design.i think its better to go for some simple circuit i guess.

got this design from instructables.i think i shld give it a try.

02-26-2008, 05:21 PM
How much current does your motor take??

02-26-2008, 06:46 PM
i guess 1.5 AMPs max.


02-26-2008, 07:14 PM
TIP 122 would do. I use to use them then, i still use them now, never smoked. :D

Design s straight forward, connect them to pic with a base resistor!!
I think that motor will take a bit less than 1A though. I am also not sure of the torque it can give. you have to get your lead screw in perfect alignment.

The simplest design will be to use a single controller. I will try putting up something of my design and vids here. but then, as usual, my promises takes a lot of time.


02-26-2008, 07:50 PM
well burning out is one reason,but also the motor movement was quite vibrating and uneven.iam not sure whether its bcz of the PIC or software.
and TIP122 is logic mosfet.can i connect it after bias resistor or do i need any transistor in between?
and what do u think of that CD4020 and CD4516 design.

and if possible pls share ur design.(circuit at least).later u can go for some detail.