Can we drive a stepper motor without datasheet ?

Discussion in 'General Electronics Chat' started by josh_mt, May 5, 2011.

  1. josh_mt

    Thread Starter New Member

    May 5, 2011
    Hi guys,

    I bought an used stepper motor, and I can't find the datasheet for this stepper motor. ( I think because it's too old )

    The only thing that I can see on the label is type of the stepper motor : PF42 - 48I5, and it is made in Japan, with "20 ohm" resistance. ( I don't know which resistance it refers to ). This stepper motor has 6 wires, which are separated to 2 groups each consists of 3 wires.

    Because I can't find the datasheet, do you think I still can drive this stepper motor ?
    Do you think there is a systematic method to know the specifications of this stepper motor ?

    Thank you guys, any answer would be appreciated.
  2. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
  3. tracecom

    AAC Fanatic!

    Apr 16, 2010
    Here's what's likely: it's a unipolar motor (because it has six wires) and becase the wires are divided into two groups, figuring out the wire connections is easier. If there is one wire in both groups that is the same color, that is probably the common.

    Here's the risky part: if you don't know the intended operating voltage, you can easily damage the motor while trying to get it to work. What did the motor come out of and can you determine from that what voltage it is intended to operate on? If not, better to start with 3 volts and gradually increase until the motor seems to be operating well without overheating.

    If you already have some experience with steppers, it will be easy, but if not, it will take a lot of reading to understand how they work. I suggest you start with this:

    Oh, and post a closeup pic of the motor.
  4. shortbus

    AAC Fanatic!

    Sep 30, 2009
  5. THE_RB

    AAC Fanatic!

    Feb 11, 2008
    You can generally determine amps and volts by the package size. Stepper motors all have fairly similar heat dissipation (Watts) per package size.

    Compare your motor to identical sized motors on the internet and find their volts/amps which tells you their Watts per phase. Your motor will ahve the same Watts you just need to determine volts/amps from the 2 known characteristics Watts and Ohms.