hi all need help with this stepper motor

hi all.....i had this 6 wire stepper motor i think the pair for the coil A (red and white red) coil B(green and white green) and the other two wire is black and white is for the common wire...my question is where should i connect the common wire..

my stepper motor has........ 2.0 curret amps....2.8 v.........1.4phase ohms should i connect the common wire to 5V supply to drive it?

You need to post a link to the specifications for the motor if you want definitive advice.

Usually a 6-wire motor can be used in either unipolar or bipolar mode (Google will explain). Bipolar mode is simpler and you don't need to connect the centre wires to anything.

I presume you have a suitable stepper motor driver board that can handle the current for your motor. I don't have anything to recommend as the Pololu A4988 that I use can't handle as much as 2 amps without overheating. However if you Google it you will get a good idea of the sort of thing you need. Higher amperage drivers are a good deal more expensive.

CAUTION Please note under NO circumstances try to power that motor from your Arduino - it will damage it because the Arduino can't supply enough current for motors.

Also, if you connect a 5v supply with lots of amps to the motor without using a current limiting driver board you will ruin the motor.

...R

zamir89: hi all.....i had this 6 wire stepper motor i think the pair for the coil A (red and white red) coil B(green and white green) and the other two wire is black and white is for the common wire...my question is where should i connect the common wire..

my stepper motor has........ 2.0 curret amps....2.8 v.........1.4phase ohms should i connect the common wire to 5V supply to drive it?

That motor has low resistance windings (1.4 ohms), so you must drive it from a bipolar chopper drive circuit, don't even think about trying to use an H-bridge or unipolar drive circuit. 2A is a lot -- you really need a proper industrial stepper-drive controller rated for 2A, none of the small single-chip chopper drivers(*) will handle 2A without overheating.

(*) A4988, DRV8835, EasyDriver, etc etc.

The reason you need chopper drive is that the back-EMF from the motor will severely limit the maximum step rate you can achieve when driven at 2.8V. To spin fast stepper motors will need a supply able to overcome the large back-EMFs, yet the winding-current must be limited to the rated value - this mandates chopper drivers that can control the current independent of the back-EMF.

is there any suggested diy driver for me are they any diagram so i can build my own driver

zamir89: is there any suggested diy driver for me are they any diagram so i can build my own driver

I doubt if you could make a DIY driver from discrete components any cheaper than buying a ready made device - certainly not when you take your time into account. It would be complicated to design and build and test and probably would not be as good as the commercial products. You need the ability to measure and limit the current flowing through the motor coils.

Building a board using (for example) the Allegro A4988 chip that is used in the Pololu board would require you to have the ability to create a pcb for surface mount components.

...R

is there any suggested diy driver for me are they any diagram so i can build my own driver

Not for that motor.

In series bipolar connection you should be able to use the Pololu DRV8825 stepper motor controller. You will not be able to drive the motor at full power and will have to set the current limit to something that the motor controller can handle (e.g. less than 1.5 amps/phase). See http://www.pololu.com/product/2133

Otherwise, as MarkT pointed out, you need an industrial motor driver. Gecko makes some that are reasonably priced.

so if i had an industrial driver.....should i connect the common wire the black and white to supply as some driver said NC...mean not connected

For motor connections, consult the detailed instructions that will come with the driver.

does ULN2003a or 2004 wll drive this type of stepper motor?

Using a h-bridge like a ULN2003 is just a bodge.

Study the manufacturers' datasheets for the ULN2003 and for the Allegro A4988 stepper driver chip to see the enormous gulf between the capabilities of the devices.

...R