Unipolar stepper motor testing...help!!

testing of stepper by battery

Hello friends...

I need some help from u guys...I am working on a project that drives UNIPOLAR STEPPER MOTORS(6 wire)...the motor is rated at 24V and i am driving it using ULN2803 which gives a logic 1 of around 5V....the problem is the motor locks at all possible step sequences...it does not move basically

To test the stepper motors I had performed a direct 12V battery test...with alternate phase shifting...it still does not move....the motors are brand new... i wud be glad if someone could help me out....

possible problems:

1.The motor is rated at 24V and i tested it 12V...could this be the problem
2.Besides the working voltages when using the motor drivers are even low.
3.I had gone wrong somewhere!!!

note: the stepper motor tht i am using are obsolete now..so no datasheet available

control post16 stepper motor circuit

ULN2803 which gives a logic 1 of around 5V

Click to expand...

???

Besides the working voltages when using the motor drivers are even low

Click to expand...

????

I had performed a direct 12V battery test

Click to expand...

How?

How did you connect the motor, when you didn't know an intended wiring?
Did you measure the windings resistances to reveal the internal circuit?

testing a stepper motor with battery

I have wired them properly....when connected them to the controller the applies Vcc to centre taps and when tested it using a 12V battery I had them open circuit and connected the two phases to the source one by one...thee connections are right i guess...

See here some ideas how to test the motor...


**broken link removed**

Sounds as you know what you're doing. I guess the motor isn't mechanical blocked and can be moved by hand (unless it hasn't a gear)? If it's a hybrid motor type, I may have get demagnetized if disassembled.

u mean to say...shud i convert the 12V supply to 24V coz the motor is rated at 24V??

No, it would at least move with 12 V supply.

here is the problem ..
it seems the no of pulses that you give to the motor is large than the motor can actually take.
so please do reduce the no of pulses per second
here is the example program that you requested
check this out
**broken link removed**